Fig. 5

The DLG motif and Kelch domain mediate TNFAIP2 interaction with KEAP1. (a) Schematic diagram of wild-type and truncated or mutant TNFAIP2 and KEAP1. (b) Co-IP assay of KEAP1 fragments interacting with TNFAIP2 in 293T cells. (c) Co-IP assay of TNFAIP2 fragments interacting with KEAP1 in 293T cells. (d) The putative motif mediates the interaction of TNFAIP2 with KEAP1 across different species. (e) Co-IP assay of the DLG motif within TNFAIP2 interacting with KEAP1 in 293T cells. (f) Co-IP analyses of NRF2 ubiquitination in HNSCC cell lines transfected with the wild-type or mutant DLG motif treated with MG132 (10 µM, 4 h). (g) Flow cytometry analyses of ROS in TNFAIP2 knockdown HNSCC cell lines rescued by expression of wild-type TNFAIP2 or the N328-520 fragment. (h-i) Cisplatin IC50 evaluations in TNFAIP2 knockdown FADU (h) and CAL33 (i) rescued by expression of wild-type TNFAIP2 or the N328-520 fragment. (j) Western blot analysis of NRF2 and its target genes in TNFAIP2 knockdown HNSCC cell lines rescued by expression of wild-type TNFAIP2 or the N328-520 fragment. Data are presented as the mean ± SEM. *** P < 0.001