FIG. 9.

Activation of Δv-JunER does not enhance D-cyclin expression. Cultures of CEFs expressing Δv-JunER or hER were rendered quiescent by culture in LS medium for 48 h in the absence of estradiol. Newborn calf serum (10%) or estradiol (2 μM) was then added as indicated, and replicate cultures were assayed for cyclin (cyc) E-cdk2 kinase activity by immunoprecipitation kinase assay (upper panel) and for expression of cyclin E, cdk2, cyclin D1, cyclin D2, cdk6, and p27^KIP1 by Western blotting (WB) (lower panel).