FIG. 3.
Expression of cyclin D1 rescues the PC3-dependent G1 arrest. NIH 3T3 cells (0.8 × 105) were seeded onto 35-mm-diameter dishes. After 24 h, cells were transfected with the expression vector pSCT-PC3 (PC3, 0.4 μg, filled bars) or pSCT-β-Gal (GAL, 0.4 μg, open bars), together with the indicated cyclins (0.8 μg) and CDKs (0.8 μg). In transfections where the CDK or the cyclin was absent, a corresponding amount (0.8 μg) of the empty CMV vector was cotransfected. Detection of transfected cells expressing PC3 or β-Gal and analysis of their DNA synthesis by measuring BrdU incorporation were performed as described in the Fig. 2A legend. At least 90 cells were scored for each experiment. The results are means ± SEM of at least three independent experiments. ∗∗∗, P = 0.0000 versus GAL; ∗∗, P < 0.0001 versus GAL; ∗, P < 0.001 versus GAL; N.S., P > 0.05 versus GAL (Student's t test).