Fig. 1: Nur77 transcriptionally upregulates TGFβ-induced ID1 expression through inhibiting Smurf2-mediated mono-ubiquitylation of Smad3.

a, b LS174T cells transfected with the indicated siRNAs for 48 h were treated with TGFβ (10 ng/mL) for the indicated time. ID1 mRNA and protein expressions were examined by qRT-PCR (a) and immunoblotting (IB) (b), respectively. si-ctr control siRNA, si-Nur77 Nur77 siRNA, hr hour. Two-way ANOVA followed by Tukey’s multiple comparisons test was used for statistical analysis, and data are presented as means ± SD (n = 3 biologically independent samples). c–e HCT116 cells were transfected with the indicated expression plasmids for 24 h or siRNAs for 48 h before SB431542 (10 μM) treatment for 1 h. Cells were then treated with TGFβ (10 ng/mL) for 1 h. Protein interactions were examined by co-immunoprecipitation (co-IP) using specific antibodies. IgG control IgG. f–l LS174T cells were transfected with the indicated expression plasmids, siRNAs, or shRNAs before TGFβ (10 ng/mL) treatment for 1 h. Chromatin immunoprecipitations were performed using control IgG or anti-Smad3 antibody followed by PCR (f). Smad3 ubiquitylation was examined by IP and IB with specific antibodies (g, i, k). Protein interactions were examined by co-IP (h, j, l). sh-ctr control shRNA, sh-Nur77 Nur77 shRNA, Ub ubiquitin. Two-way ANOVA followed by Tukey’s multiple comparisons test was used for statistical analysis, and data are presented as means ± SD (n = 4 biologically independent samples). Data represent at least two independent experiments. Source data are provided as Source Data file.