Fig. 6: STAT3 regulated Dlx5 transcription by promoting the activity of its promoter.

a Illustration of predicted STAT3 binding sites on the Dlx5 promoter. b ChIP assay for occupation of STAT3 on the promoter of Dlx5 in the C3H10 cell line. IgG n = 3, STAT3 n = 9. c Effect of STAT3, constitutively-active STAT3 (STAT3-C) and dominant-negative mutation of STAT3 (STAT3-DN) on Dlx5 promoter activity. Dlx5 promoter-driven luciferase reporter was co-transfected with STAT3, STAT3-C, and STAT3-DN expressing plasmid separately in the 293T cell line. After 48 h, the luciferase activity was performed in cell extract supernatants. n = 3. d Effects of potential STAT3 binding site mutations on the activity of Dlx5. STAT3 was co-transfected with the luciferase reporter driven by the Dlx5 promoter (DLX5-Luc) or mutant Dlx5 promoter (Dlx5 promoter with deletion of the two predicted STAT3 binding sites, DLX5-mu-Luc) separately in the 293T cell line, followed by luciferase activity analysis. n = 3. e Co-IP analysis of STAT3 and MSX1. Myc-MSX1 expressing plasmid was co-transfected with or without Flag-STAT3 in the 293T cell line. After 48 h, the whole-cell lysate was used for immunoprecipitation and then immunoblotted with the indicated antibodies. f Co-IP of STAT3 with MSX2. The Co-IP was repeated twice to similar results. g Effect of STAT3 activity on the synergistic promotion of STAT3 and MSX1 on Dlx5 promoter activity. MSX1 and DLX5-Luc were co-transfected with STAT-C or STAT3-DN into the 293T cell line followed by luciferase activity analysis. n = 3. h Effect of STAT3 binding sites on the synergistic promotion of STAT3 and MSX1 on the Dlx5 promoter activity. STAT3-C and MSX1 were co-transfected with the luciferase reporter driven by the Dlx5 promoter or mutant Dlx5 promoter into the 293T cell line, followed by luciferase activity analysis. n = 3. i Four mutants (R382W, R382Q, V637M, and T714A) were shown on the STAT3 domains. j Effect of STAT3 wild type (WT) and four mutants (R382W, R382Q, V637M, and T714A) on Dlx5 promoter activity. n = 3. k Effect of various STAT3 mutants activity on the synergistic promotion of STAT3 and MSX1 on Dlx5 promoter activity. n = 3. Two-tailed Student’s t test. Data represent the mean ± s.d. Source data are provided in the Source data file.