Recombinant Bac-GV2 DNA was obtained by inserting a fused gfp gene with the Bacillus thuringiensis vip2A(c) gene encoding a possible enzymatic component under the control of the polyhedrin gene promoter of the baculovirus Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). The Trichoplusia ni cell line TnHi5 was transfected with Bac-GFP and Bac-GV2 DNAs respectively. Fluorescent cells expressing the fusion protein GV2 were much fewer than those expressing green fluorescent protein (GFP) alone, and did not obviously increase in number from 2 to 5 days after transfection. This result showed that the Vip2A fusion protein might have an ADP-ribosylating activity on cell skeleton actin, exerting an influence on the production and diffusion of the budded virus from insect cells.