FIG. 7.

(A) Effects of the expression of DNp110, DNp85, or WTp110 on the induction of cyclin D1 protein by bFGF, PDBu, or serum. The experiments were performed as described in the legend to Fig. 1 except that the serum-deprived, transfected cells were stimulated with bFGF, PDBu, or serum for 9 h. Percentages of cyclin D1-positive cells in the transfected population were determined under a fluorescence microscope as described in Materials and Methods. (B) Coexpression of WTp110 relieves the inhibitory effect of DNp110, DNp85, or BDKD on bFGF-induction of cyclin D1. The cells were cotransfected with 1.0 μg of the expression plasmid for either of the DN forms or 1.7 μg of either pMIKNeop110 or an empty vector, together with 0.3 μg of pCAGGS-βgal, made quiescent, and then stimulated with bFGF for 9 h.