Mapping interactions of Chikungunya virus nonstructural proteins.

The four nonstructural proteins (nsPs1-4) of Chikungunya virus (CHIKV) play important roles involving enzymatic activities and specific interactions with both viral and host components, during different stages of viral pathogenesis. Elucidation of the presence and/or absence of interactions among nsPs in a systematic manner is thus of scientific interest. In the current study, each pair-wise combination among the four nonstructural proteins of CHIKV was systematically analyzed for possible interactions. Six novel protein interactions were identified for CHIKV, using systems such as yeast two-hybrid, GST pull down and ELISA, three of which have not been previously reported for the genus Alphavirus. These interactions form a network of organized associations that suggest the spatial arrangement of nonstructural proteins in the late replicase complex. The study identified novel interactions as well as concurred with previously described associations in related alphaviruses.