Alphaviruses including chikungunya virus, Ross River virus and the model Semliki Forest virus are enveloped viruses with a single-stranded, positive sense RNA genome, that are transmitted to humans and a variety of mammals by insects, often mosquitos. Currently no antiviral therapy or vaccines exist for alphavirus infections. Although some members of the group have been very well studied, the functions of the alphaviral non-structural protein (nsP) 3 have been poorly understood. Recently we have described interactions between alphavirus nsP3 and several host proteins which affect the cellular environment in a manner favourable to viral replication. In this talk, I will describe our work on the host protein G3BP, which is sequestered by nsP3 to inhibit the formation of RNA stress granules and also to direct the correct architecture of the viral replication complexes. I will also describe our work on the activation of the PI3K-Akt-mTOR pathway by nsP3 and its role in pathogenesis.
Published on October 8, 2021