Fig. 6: NEDD4 mediates K48-linked ubiquitination of ZBTB7B at lysine 450 to promote its proteasomal degradation.

A The ubiquitination levels of ZBTB7B in BEAS-2B, H1299, and A549 cells were determined by IP and western blot. B The ubiquitination levels of ZBTB7B in H1299 cells were determined by IP and western blot after NEDD4 knockdown. C The ubiquitination levels of ZBTB7B in H1299 cells were assessed by IP and western blot after NEDD4 overexpression was determined. D, E The levels of K48-linked and K63-linked ubiquitination of ZBTB7B in H1299 cells were assessed through immunoprecipitation and western blot following NEDD4 overexpression. F Ubiquitination levels of wild-type ZBTB7B and ZBTB7B mutant were determined by IP and western blot. G Stability of wild-type ZBTB7B and ZBTB7B K450R mutant was examined by CHX chase assay. H The ubiquitination levels of ZBTB7B K450R mutant following NEDD4 overexpression were determined by IP and western blot. I Stability of ZBTB7B K450R mutant following NEDD4 overexpression was determined by CHX chase assay. Data are presented as mean ± SD of at least three independent experiments. ns p > 0.05, *p < 0.05, **p < 0.01.