FIG. 3.

Infectivity of TV. (A) Media from cells transfected with capped RNA or uncapped RNA 48 h posttransfection were used for inoculation of cells. Only capped TV RNA yielded infectious virus. The images were taken at 24 or 72 h after incubation with virus-containing media. (B) Detection of TV RNA by RT-PCR. Lane 1 (M), DNA kilobase marker; lanes 2 to 7, RNA isolated from cells infected with serially diluted viral stocks; lane 8 (−), negative control of RT-PCR, in which the RT reaction step was omitted; lane 9 (+), RT-PCR positive control. (C) Detection of nonstructural proteins in transfected cells. The preimmune serum used as a control in the immunofluorescence analysis was collected from the mouse prior to injection with purified TV RdRp protein. ab, antibody.