The cytoplasmic tail substitution increases the assembly efficiency of Ebola virus glycoprotein on the budded virus of Bombyx mori nucleopolyhedrovirus

Glycoprotein (GP 1,2 ) of the Ebola virus (EBOV) is the key membrane fusion protein, which is a key candidate protein for vaccine preparations. Previously, GP 1,2 was expressed by Bombyx mori nucleopolyhedrovirus (BmNPV) expression vector system; however, few GP 1,2 was incorporated into budded virus (BV) of BmNPV. To improve the incorporation efficiency of GP 1,2 into the virion, the GP 1,2 fusion with the cytoplasmic tail of GP64 of BmNPV was expressed in BmN cells by the BmNPV expression system. The BV was purified by ultracentrifugation, and GP 1,2 expression in BV was detected by the antibody. The result indicated that a 532% increase in the relative GP 1,2 densitometry signal was observed in constructs utilizing the GP64 C-terminal domain; moreover, the substitution of GP 1,2 native signal peptide with GP64 signal peptide increased the incorporation efficiency by 34.6% in the relative GP 1,2 densitometry signal. We revealed that the application of the cytoplasmic tail of BmNPV GP64 significantly increased the incorporation rate of GP 1,2 into the BV envelope. This study lays a foundation for GP 1,2 vaccine development. • Recombinant Ebola virus glycoprotein GP 1,2 was incorporated into the budded virus envelope of BmNPV. • Application of the cytoplasmic tail of BmNPV GP64 significantly increased the incorporation rate of GP 1,2 into the BV envelope. • GP64 signal peptide substitution improves the incorporation rate of GP 1,2 into the BV envelope.