Figure 1.

TMEPAI induces the degradation of c-Maf but not MafA and MafB. A, the c-Maf plasmid was co-transfected with individual plasmids for 24 h, followed by total protein extract and immunoblotting assay. Lane 1, pcDNA3.1; lane 2, LRSAM1; lane 3, TRIM25; lane 4, RNF31; lane 5, UBE3C; lane 6, TRIM44; lane 7, RNF10; lane 8, RNF32; lane 9, RNF125; lane 10, MKRN2; lane 11, TRIM9; lane 12, TRIM11; lane 13, TMEPAI; lane 14, pcDNA3.1; lane 15, HERC4; lane 16, TMEPAI. B, c-Maf was co-transfected with TMEPAI at the indicated concentrations into HEK293T cells for 24 h, followed by immunoblotting assay. C, c-Maf and TMEPAI plasmids were co-transfected into HEK293T cells with the indicated incubation times followed by immunoblotting assay. D, c-Maf and TMEPAI plasmids were co-transfected into HEK293T cells followed by CHX treatment for indicated periods. All cell lysates were subjected to immunoblotting assay as indicated. E, densitometric analysis of c-Maf in the presence of TMEPAI and CHX treatment from D. F and G, MafA (F) or MafB (G) and TMEPAI plasmids were co-transfected into HEK293T cells for 24 h followed by immunoblotting assay. H, TMEPAI was knocked down in MM cell lines LP1 and RPMI-8226 by siTMEPAI for 48 h, followed by immunoblotting assay. I, LP1 and RPMI-8226 cells were subjected to TMEPAI knockdown by siRNA. Forty-eight hours later, the cells were treated with CHX for indicated periods and immunoblotting assay.