Fig. 6: RNF128 promotes the degradation of S100A8 by autophagy.

A Western blot analysis of S100A8 expression in THP-1 cells stably overexpressing RNF128-Flag treated with or without LPS (200 ng/ml) for 8 h. B Western blot analysis of S100A8 expression in stable RNF128-knockout THP-1 cells treated with or without LPS (200 ng/ml) for 8 h. C THP-1 cells were co-transfected with S100A8-GFP and increasing concentrations of RNF128-Flag for 48 h. The expression of S100A8-GFP was analyzed by western blot. D THP-1 cells stably overexpressing RNF128-Flag were transfected with GFP-S100A8 and incubated with CHX for the indicated time. The expression of S100A8-GFP was analyzed by western blot. E Rnf128^+/+ and Rnf128^−/− BMDMs were stimulated with LPS (200 µg/ml) for 8 h and subsequently treated with cycloheximide (100 µg/mL) for the indicated time. The expression of S100a8 was detected by western blot. F THP-1 cells stably overexpressing RNF128-Flag were transfected with S100A8-GFP and treated with MG132, CQ, 3-MA, or NH₄Cl. The expression of S100A8-GFP was analyzed via western blot. G THP-1 cells stably overexpressing RNF128 were treated with CQ (50 mM) for 4 h. The expression of S100A8 was detected by western blot. H THP-1 cells stably overexpressing RNF128 were treated with wortmannin (WM, 10 μM) for 12 h. The expression of S100A8 was detected by western blot. I THP-1 cells with stable ATG7 knockout or control cells were transfected with RNF128-Flag for 48 h. The expression of S100A8 was measured by western blot. J THP-1 cells with stable ATG5 knockout or control cells were transfected with RNF128-Flag for 48 h. The expression of S100A8 was measured by western blot.