FIG. 4.
Effects of large-T and small-t antigens on cyclin inhibitors p21WAF1 and p27KIP1. Confluent monolayers of HDF cells were serum stimulated or infected as described for Fig. 2 and 3. The experiments shown in the three panels were performed at different times. (A) Cells were extracted at 27 h postinfection, and then 50 μg of protein from each extract was used for Western blot analysis of the CKI p21WAF1. (B) Cells were extracted at 20, 28, and 34 h postinfection, and then extracts were analyzed for p27KIP1 as for panel A. (C) Cells were treated with serum or infected for 32 h and then were extracted for p27KIP1 analysis.