Proteolytically activated PKCδ-CF contributes to PKD1 phosphorylation. N27 dopaminergic cells treated with H2O2 (100 μM) for 30, 60 or 90 minutes were monitored for PKCδ-CF (A). N27 dopaminergic cells were treated with H2O2 ± DEVD-fmk (50 μM) and ± ZVAD-fmk (50 μM and 100 μM) for 60 min and monitored for PKD1 activation and PKCδ cleavage (B). N27 dopaminergic cells stably expressing the cleavage-resistant mutant of PKCδ (PKCδD327A) were treated with H2O2 and monitored for PKD1 activation (C). PKD1 activation was monitored in N27 dopaminergic cells transfected with the catalytic fragment of PKCδ (PKCδ-CF) and the regulatory fragment of PKCδ (PKCδ-RF). Additionally, the mock transfection group treated with or without H2O2 was also monitored for PKD1 activation (D).