Fig. 5

USP22 enhances the stability of CSN5. a A549, H1792 cells were transfected with control (CTRL) or USP22 siRNA for 24 h and then subjected to western blot analysis. b H1792 cells were transfected with control (CTRL) or USP22 siRNA for 24 h before RNA was extracted and subjected to reverse transcript PCR (RT-PCR). Protein and mRNA level of USP22, CSN5, PD-L1 were assesses using western blot and agarose gel electrophoresis respectively. mRNA levels were determined by image J. Error bars represent SD (n = 3), ***P < 0.001. Statistical differences were determined by two-sided Student’s t-test. c A549, H1792 cells were transfected with pcDNA3.1-USP22-HA plasmid for 24 h and then subjected to western blot analysis. pcDNA3.1 empty vector was transfected as control. d CSN5 protein level were measured upon USP22 knockdown with or without proteasome inhibitor MG132 in H1792 cells. e A549 cells were transfected with control (CTRL) or USP22 siRNA for 24 h followed by cycloheximide (CHX) (20 μg/ml) for indicated time. Relative protein abundance was measured by image J. Experiments were repeated three times. f A549 cells were transfected with pcDNA3.1 empty vector or pcDNA3.1-USP22-HA plasmid for 24 h followed by cycloheximide (CHX) (20 μg/ml) for indicated time. Relative protein abundance was measured by image J. Experiments were repeated three times