FIG. 4.

Binding of ³⁵S-labeled GDVII or DA virus to proteins extracted from BHK-21 cells. The proteins (100 μg) were separated by 2D gel electrophoresis. (A) Staining with Coomassie blue. (B and C) The proteins from polyacrylamide gels run in parallel were transferred onto nitrocellulose membranes. The membranes were incubated in blocking buffer containing 5% milk powder and then incubated for 1 h with 10⁶ cpm of radioactive GDVII (B) or DA (C) virus. After three washes with blocking buffer without milk, the membranes were exposed for a few hours to the screen of a PhosphorImager.