Figure 5: Dullard-mediated inhibition of BMP signalling is cell-autonomous.

(a) Western blot analysis of three independent C3H10T1/2 clones transfected with the empty vector (C-1, C-2 and C-3) or the vector containing Flag-tagged Dullard (D-1, D-2 and D-3). (b) Dullard overexpression inhibits BMP-dependent phosphorylation of Smad1/5/8 in C3H10T1/2 cells. Each clone was treated with rhBMP4 (50 ng ml⁻¹) for 30 min, and the lysate was immunoblotted with antibodies for the indicated proteins. (c) Dullard overexpression inhibits Sox9 upregulation in C3H10T1/2 cells after 3 days of incubation with BMP4 (50 ng ml⁻¹). (d) Two each of wild-type and Dullard-null ES clones were treated with rhBMP4 (50 ng ml⁻¹) for 30 min, and their lysates were immunoblotted with antibodies for the indicated proteins. Note the enhanced p-Smad1/5/8 in the Dullard-null ES cells.