Analysis of VP22-EYFP, VP22, and EYFP in transiently transfected COS-7 cells by Western blotting. The proteins were probed with both VP22- and EYFP-specific polyclonal antibodies. The molecular weight of each protein is indicated in the right margin. Lane 1, VP22-EYFP; lane 2, VP22; lane 3, EYFP. Mr standards are shown in the left margin.