FIG. 4.

Phosphorylation of the viral phosphoprotein in Vero cells persistently infected with the recombinant BDV expressing either P-AASS or P-DDSS. Uninfected Vero cells or Vero cells persistently infected with either rBDV-wt or rBDV-AASS or rBDV-DDSS were labeled with [³²P]orthophosphate for 4 h (left) or 22 h (right). P was subsequently immunoprecipitated, separated by SDS-PAGE using a 15% gel, and transferred to a nitrocellulose membrane. The upper panel represents an autoradiography showing the levels of radioactive labeled P. The lower panel shows the detection of total P by P-specific antibodies. The immunoglobulin G (IgG) heavy chain detected by the secondary antibody is indicated. Numbers at the bottom give the ratio of ³²P-labeled P (³²P) to levels of total P detected by Western blot analysis. The ratio of ³²P/total P observed with P-wt was set to 1.