Analysis Of The Composition Of BmNPV Budded Virus Envelope Protein

Bombyx mori nucleopolyhedrovirus(BmNPV)is a viral pathogen that seriously endangers sericulture.The BmNPV genome is highly similar to the Autographa californica nucleopolyhedrovirus(AcMNPV)genome,but can only infect the silkworm.The current research has made great progress in the field of AcMNPV invasion and budding release,but there are few studies on the mechanism of BmNPV BV particles entering the host and its budding mode.Studies have shown that viral invasion of host cells and budding release process is a relatively reversible process.The invasion of envelope virus is closely related to the envelope protein of the virus surface.GP64 is a membrane fusion protein of group I baculovirus,localized on the cell membrane,virus The particles bud at the cell membrane to obtain the capsule structure and the virus-encoded protein such as GP64 distributed on it,and GP64 mediates the initiation of infection of the bud virus into the cell during the virus invasion process.We have previously found that GP64 localizes on the cell membrane or in the cytoplasm to produce infectious BV,the mechanism of which is still unclear.In this paper,two different GP64 protein BV capsule components were studied to explore the mechanism of BV formation and provide a basis for the baculovirus budding mechanism.Below are key research findings:Firstly,the vGP64 and vSPIIGP64 BV envelope proteins constructed and obtained in the laboratory were isolated and identified by mass spectrometry.Among the two viruses,30 kinds of viral proteins were detected together,of which 6 were significantly different,75 were host proteins detected,and 4 virus-specific proteins were detected in vGP64 virus,11 hosts.Specific protein;one virus-specific protein,five host-specific proteins were detected in vSPIIGP64 virus,and then the differential virus proteins identified by mass spectrometry were subjected to western-blot verification analysis.Secondly,the cell lines with different eGFP localization were constructed.The distribution of eGFP in the BV envelope formed by the infection of the two viruses preliminarily predicted that the BV capsule was derived from the endometrial system.Absolute quantitative analysis of the two viral BV genomes.The study found that the same quality of DNA produced different virus titers,the mutant titer is low,indicating that some BV may not be infectious.Finally,by electron microscopy analysis of the cells infected with the two viruses,itwas preliminarily determined that there were two ways of budding after BmNV infection of BmN cells.Through the above studies,we initially revealed the differences in the composition of the two viral envelope proteins,and initially verified the differences in the budding modes of the two viruses,providing a reference for further study on the budding mode of BmNPV.