The Preliminary Functional Analysis Of Px26 Gene Of Plutella Xylostella Granulovirus

Baculoviruses are classified as a group of arthropod-specific viruses with circular, double-stranded DNA.Envelope fusion protein of the viruses is a major structural protein,which can mediate the entry of virus and may affect the host range.The BVs(budded virions) of baculovirus have two different types of envelope fusion proteins:GP64 and F protein.GP64 is essential for groupâ… NPV BV,which can mediate membrane fusion under the condition of low-pH-triggered and is necessary for efficient virion budding from the cell surface.The envelope fusion protein encoded by groupâ…¡NPV and GV is named F protein,such as LD130,SE8 and AgseF.But the envelope protein encoded by groupâ… NPV and homolog of the F protein is named F homologous protein,such as AC23 and OP21.Like GP64,F protein of groupâ…¡NPV and AgseGV possess pH-triggered membrane fusion activity,and mainly located on the cell membrane of the cells transfected.Plutella xylostella granulovirus(PlxyGV) is mainly pathogenic to the diamondback moth.Like groupâ…¡NPVs and AgseGV,there is not a homolog of gp64 gene in PlxyGV genome.But it is found that orf26(Px26) of PlxyGV was homologous to AgseGV f gene with high sequence similarity.A recent research report indicated that AgseGV f gene could functionally substitute gp64 of Autographa californica multiple nucleopolyhedrovirus(AcMNPV).Thus,in order to detect the functional attribute and the location of the predicted encoding product of Px26,transient expression plasmid of Px26,fused with a copy of the gene of enhanced green fluorescent protein(EGFP),was separately transfected into some insect cell lines.It was shown that Px26-EGFP mainly positioned on the cell membrane of cells transfected with the transient expression plasmid of the fused gene Px26-egfp,but cell membrane fusion was not observed.Lamda-Red recombination system was mainly used for the study of the genome of E.coli.In recent years,with the development of baculovirus shuttle vector,this kind of recombinant system has been become a powerful tool for identifying gene function of baculovirus.The second part of this paper is to knock out gp64 of AcMNPV Bacmid by use of Lamda-Red recombination system and the analysis of transfection-infection, obtaining the recombinant bacmid.It will lay the basis of detecting the Px26 gene and identifying other exogenous gene function.The work is under way.