Fig. 3.

Peptide inhibition of GRK2 (a), and GRK5 (b) phosphorylation of tubulin. Phosphorylation of tubulin (0.5 μM) was determined by incubation with purified GRK2 and GRK5 in the absence (Ctrl) or presence of peptide inhibitors at the indicated concentrations as previously described (Baameur et al. 2010). Data shown are the mean ± SEM for four or more experiments performed in duplicate and normalized to the % of control. Comparison to Ctrl was performed by One-Way ANOVA; ***P < 0.001, **P < 0.01, and *P < 0.05