Studying Viral Replication using Orthobunyavirus N protein Chimeras
Category: Research Poster
Author(s): Riley George
Presenter(s): Riley George
Mentors(s): Mark Stenglein, Charlize Geer
Orthobunyaviruses are notable human and animal pathogens causing syndromes ranging from self-limiting febrile illness to hemorrhagic fever. These viruses have a trisegmented, negative sense RNA genome that allows for reassortment when a host cell is coinfected by two related viruses. The resulting reassortant viruses may be more pathogenic than the parental viruses. However, the protein interactions limiting reassortment are not well defined. The interactions between the viral polymerase (L protein) and viral nucleoprotein (N protein) enable transcription of viral RNA and are vital to viral replication. Past experiments show that N proteins function with L proteins of closely related viruses, yet N proteins lacking shared amino acid identity function suboptimally. To determine which N protein residues are important for L-N function, we combined a portion of one high-functioning and one low-function N protein, creating chimeric N proteins. Chimeras from La Crosse Virus (LACV) and Trivittatus virus (TVTV) were tested with the LACV L protein using minigenome assays. This method expresses viral proteins in mammalian cells, measuring their activity through luminescence. We hypothesized that these chimeras would increase the function of the TVTV N protein to the level of the LACV N protein. We found that the location of amino acid changes in the N protein chimeras can increase L-N function, but some lost the ability to function, possibly due to inhibition of N-N interactions.