FIG. 4.

IFN induced formation of pY701-Stat1 and the antiviral (VSV) state. (A) BF cells were infected (or not) with 20 PFU of the various rSeVs per cell as indicated above and treated (or not) with 1,000 U of IFN-α per ml at 24 hpi, as indicated. Total cell extracts were prepared 40 min later, separated by SDS-PAGE, and immunoblotted with anti-Stat1 (top), anti-pY701-Stat1 and anti-actin (middle), and anti-C (bottom). A timeline of the experiment is shown at the top of the figure. (B) BF cells were infected (or not) with 20 PFU of the various rSeVs per cell as indicated above and treated (or not) with 1,000 U of IFN-α per ml at time zero, as indicated. All of the cultures were infected with 50 PFU of VSV per cell at 24 hpi. The cells were harvested at 28 hpi, and the levels of VSV P protein in cytoplasmic extracts were determined by immunoblotting. An anti-actin antibody was included as a loading control. A timeline of the experiment is shown above.