Fig. 7

PSMD7 stabilizes SOX2 protein expression via suppressing SOX2 degradation mediated by proteasome. (A) and (B) SOX2 protein levels at various times were measured by western blotting after MG132 addition (10 µM) to SW 1990 and PANC-1 cells. (C) and (D) Western blot analysis of SOX2 and PSMD7 protein expression in PANC-1 cells transfected with shPSMD7 or shNC and SW 1990 cells transfected with exogenous PSMD7 or a control vector, with or without treatment with 10 µM MG132. (E) and (F) PANC-1 cells transfected with shPSMD7 or shNC and SW 1990 cells transfected with exogenous PSMD7 or a control vector were subjected to treatment with 20 µg/mL CHX, followed by assessment of SOX2 protein levels using western blotting. n = 3, **p < 0.01. (G) and (H) PANC-1 and SW 1990 cells were treated with shPSMD7 or PSMD7 for 72 h and the intracellular proteasome activity in the treated cells were assessed using proteasome activity fluorometric assay kit. Experiment was repeated three times. A statistically significant difference in the proteasome activity in cells treated with SAHA vs. without SAHA (control) is denoted by *p < 0.05, **p < 0.01. (I) and (J) Lysates of SW 1990 along with PANC-1 cells that were transfected with Flag-PSMD7, sh-PSMD7, and HA- ubiquitin (HA-Ub) were analysed via immunoblotting and then immunoprecipitated using anti-SOX2 and probed with anti-HA. *p < 0.05, **p < 0.01