Fig. 8.

Roscovitine probably reduced [³H]DA uptake into YFP-HA-hDAT PAE cells in a Cdk5-independent manner. PAE cells stably expressing YFP-HA-hDAT were transfected with NT-siRNA or increasing concentrations of Cdk5-siRNA as described under Materials and Methods. Cells were processed for experiments 72 h after transfection. A, effect of increasing concentrations of Cdk5-siRNA on PAE Cdk5 protein levels are shown. Top, representative immunoblots of Cdk5 and β-actin. Bottom, bands were quantified by densitometry. Data represent mean values ± S.E.M. for n = 3 independent experiments. **, p < 0.01 compared with cells transfected with NT-siRNA (one-way ANOVA followed by Bonferroni's multiple comparisons post-test). B, specific [³H]DA uptake into PAE cells was measured in the absence or presence of roscovitine (30 μM) from cells transfected with increasing concentrations of Cdk5-siRNA. Data are presented as a scatter plot with individual symbols representing the average from an independent experiment performed in duplicate. Solid lines represent the mean for the n = 3 independent experiments for each condition. Dashed line represents vehicle (0.1% DMSO) control. *, p < 0.05 and **, p < 0.01 compared with respective vehicle control (repeated measures two-way ANOVA followed by Bonferroni's multiple comparisons post-test).