The protein-protein interactions between Amsacta moorei entomopoxvirus (AMEV) protein kinases (PKs) and all viral proteins

Abstract

Entomopoxviruses are an important group of viruses infecting only insects. They belong to Poxviridae which infect both invertebrates and vertebrates, including humans. Protein kinases are known to have roles at virus morphogenesis, host selectivity, the regulation of cell division and apoptosis in some vertebrate poxviruses. In this study, 2 protein kinases (PKs) (AMV153 and AMV197) of Amsacta moorei entomopoxvirus (AMEV) were investigated for the interactions among 230 viral proteins using yeast two-hybrid system (Y2H). For this purpose, two protein kinases and 230 viral genes were cloned into the bait and prey vectors, respectively. Bait vectors were introduced into Saccharomyces cerevisiae AH109. Expression of the bait genes were confirmed by western blot analysis. Both yeast strains of bait were transformed individually with each prey clone and grown on a selective medium (minimal synthetic defined) to determine the protein–protein interactions between bait and prey proteins. Transformations identified totally 16 interactions among AMEV protein kinases and all viral proteins of which 5 belong to AMV153 and 11 belong to AMV197. One of the five interactions detected for AMV153 protein kinase is self-association. Its other four interactions are with two virus entry complex proteins (AMV035 and AMV083), a membrane protein (AMV165) and a subunit of RNA polymerase (AMV230). The other protein kinase, AMV197, interacted with two virus entry complex proteins (AMV035 and AMV083) as AMV153, a caspase-2 enzyme (AMV063), a Holliday junction resolvase (AMV162), a membrane protein (AMV165), a subunit of RNA polymerase (AMV230) and five other hypothetical proteins (AMV026, AMV040, AMV062, AMV069, AMV120) encoded by AMEV genome. Glutathione S-transferase (GST) pull-down assay was used to confirm all interactions described by Y2H analysis. In addition, the theoretical structures of the two of 16 interactions were interpreted by docking analysis. Consistent with Y2H and pull down assays, docking analysis also showed the interactions of AMV063 with AMV153 and AMV197. Detected interactions of the AMEV viral proteins with viral protein kinases could lead to the understanding of the regulation of the viral activities of interacted viral proteins.