Fig.Figure 3A. Parental HEK293T, HET and HOM1 cells were treated with high (20 ng/mL) or low (1.25 ng/mL) concentrations of Activin A for 1 h, in the presence or absence of either 1 µM LDN-193189 or 10 µM SB-431542. Quantifications are the levels of pSMAD1/5 normalized to the loading control (Actin), expressed as fold change relative to untreated for each clone. Quantifications are the average normalized intensities ± SEM of 3 independent experiments. Data information: In all panels, Western blots of whole cell lysates were probed with the antibodies indicated. hi, high; Act, Activin A; SB, SB-431542; LDN, LDN-193189. The p-values (for A, B and D) are from a t-test with Holm-Sidak correction, for comparison between indicated pairs. ns, not significant; *, p< 0.05; **, p<0.01, ***, p<0.001; ****, p<0.0001. The p-values in C are from two-way ANOVA with Tukey's post hoc correction. B. Parental HEK293T, HET and HOM1 cells were treated with either Activin A or BMP4/7 (both at 20 ng/mL) for 1 h, in the presence or absence of either 1 µM LDN-193189 or 10 µM SB-431542. Quantifications are the levels of pSMAD1/5 normalized to the loading control (Actin or Tubulin), expressed as fold change relative to untreated for each clone. Quantifications are the average normalized intensities ± SEM of 3-5 independent experiments. Note that the Activin A quantifications also includes data generated with high dose Activin A in Fig. 3A as they are independent replicates. Data information: In all panels, Western blots of whole cell lysates were probed with the antibodies indicated. hi, high; Act, Activin A; SB, SB-431542; LDN, LDN-193189. The p-values (for A, B and D) are from a t-test with Holm-Sidak correction, for comparison between indicated pairs. ns, not significant; *, p< 0.05; **, p<0.01, ***, p<0.001; ****, p<0.0001. The p-values in C are from two-way ANOVA with Tukey's post hoc correction. C. ICR-B169 and HSJD-DIPG-007 cells were treated with either Activin A or BMP4/7 (both at 20 ng/mL) for 1 h, in the presence or absence of either 1 µM LDN-193189 or 10 µM SB-431542. Quantifications are the levels of pSMAD1/5 normalized to the loading control (Actin) expressed as fold change relative to BMP4/7 induction in each clone and are the average normalized intensities ± SEM of 3 independent experiments. Data information: In all panels, Western blots of whole cell lysates were probed with the antibodies indicated. hi, high; Act, Activin A; SB, SB-431542; LDN, LDN-193189. The p-values (for A, B and D) are from a t-test with Holm-Sidak correction, for comparison between indicated pairs. ns, not significant; *, p< 0.05; **, p<0.01, ***, p<0.001; ****, p<0.0001. The p-values in C are from two-way ANOVA with Tukey's post hoc correction. D. Parental HEK293T, ACVR1B/C dKO, HOM1 and HOM1 ACVR1B/C dKO cells were treated with 20 ng/mL Activin or BMP2 for 1 h. Quantifications are the average intensities of pSMAD1/5 normalized to Actin ± SEM of 3 independent experiments. Data information: In all panels, Western blots of whole cell lysates were probed with the antibodies indicated. hi, high; Act, Activin A; SB, SB-431542; LDN, LDN-193189. The p-values (for A, B and D) are from a t-test with Holm-Sidak correction, for comparison between indicated pairs. ns, not significant; *, p< 0.05; **, p<0.01, ***, p<0.001; ****, p<0.0001. The p-values in C are from two-way ANOVA with Tukey's post hoc correction.