Control of host gene expression by Cotesia plutellae bracovirus

An endoparasitoid wasp, Cotesia plutellae, parasitizes larvae of the diamondback moth, Plutella xylostella. The parasitoid wasp induces significant alteration in host gene expression with its symbiotic polydnavirus, C. plutellae bracovirus (CpBV). A viral histone H4 encoded in CpBV alters host gene expression at transcriptional level when it is transiently expressed in nonparasitized larvae. Its aberrant long N-terminal tail may be responsible for its control of host gene expression by an epigenetic mode. CpBV15β is a host translation inhibitory factor (HTIF) encoded in the virus. It shares structural similarity with a translation initiation factor, eIF4G. Immunoprecipitation with CpBV15β antiserum suggests that CpBV15β can sequester eIF4A, which is required for unwind the secondary structure at 5’UTR of target mRNAs. These findings suggest that CpBV can alter host gene expression in both transcription and translation levels.