FIGURE 3.

Phosphorylation blockage enables agonists to use PKCϵ for ERK phosphorylation. Cells were treated with DMSO or 50 μm PKCϵ-specific inhibitor (PKCϵi) for 3 h. HEKOPRM1 (A) and HEK3A cells (B) were then treated with agonists as in Fig. 1. ERK phosphorylation was determined by normalizing the immunoreactivities of phosphorylated ERK against the immunoreactivities of total ERK. The results were further normalized against that in the control with DMSO.