FIG. 2.

RK-BARF0 binds and induces proteasome-dependent degradation of epithelin precursor. (A) H1299 cells transiently transfected with Flag and His6-tagged RK-BARF0, RK-158, or RK-179 or with epithelin precursor were induced with CdCl₂. Lysates were directly loaded onto an SDS-PAGE gel (left panel) or were immunoprecipitated with α-Flag (right panel). RK-BARF0 was detected with α-His6, and epithelin precursor was detected with α-cMyc. (B) H1299 cells transiently transfected with a combination of RK-BARF0 or RK-158 and epithelin precursor (Epi-P) were induced with 5 μM CdCl₂ and treated with 20 μM MG132 or DMSO control. Epithelin precursor was detected by immunoblot with α-cMyc. (C) H1299 cells transiently transfected with RK-BARF0 or RK-158 and epithelin precursor (Epi-P) or A20 were used for immunoblot. RK-BARF0 was detected with α-His6, and epithelin and A20 were detected with α-cMyc. IP, immunoprecipitation; WB, Western blot.