Microplitis Bicoloratus Bracovirus Regulates The Host NF-κB And EIF4F

Microplitis bicoloratus carries polydnavirus, It is predominantly expressed in vivo to suppress host immune responses by polydnavirus. In invertebrates, NF-κB signaling pathway transcription is suppressed by PDV. Because IκB-like genes (Vankyrin) structure is similar with Dorsal. It can effectively compete with Cactus, combined with Dorsal. Inhibition of NF-κB signaling pathway, It found that after the NF-κB transcription signaling pathway is inhibited, the downstream eIF4F will be reduced.Thereby inhibiting the immune response of the host.In this study, we got Relish, Dorsal, Cactus and eIF4F Sequences from the Spodoptera litura hemocytes transcriptom.Also got Vankyrin86,Vankyrin92and Vankyrin101Sequences from the Microplitis bicoloratus polydnavirus genome data. Determined by the conserved domains of Relish, Cactus and Vankyrin family have ANK domains, Proved their structural similarity。 we constructed expression vectors for prokaryotic and eukaryotic system, demonstrated Vankyrin expressed in E.coli and lepidopteran insect cell lines with Western blot. Determining Vankyrin101protein location and the effect on the cells by immunofluorescence. And got hemocytes cDNA of S. litura with7days post-parasitization, detected the expression of IκB-like, Relish, Dorsal, Cactus and eIF4F. We extracted proteins of S.litura with4-7days post-parasitization, By purchasing eIF4F specific antibodies, After detecting its expression in the parasitic, Found expression eIF4F complexes are reduced. Then we detected the eIF4A expression in different tissues:hemocytes, nerve, fatbody, midgut, ovary and testis. eIF4A found highly expressed in the fat body and ovary. Explain eIF4A important role in immune response and reproduction. At the same time found eIF4A and ATPase β there is close relationship.