Fig 6.

Smad4 is not responsible for TGF-β's inhibitory effects on BMP responses. MDA-MB-231 or MDA-MB-468 cells were transiently transfected with BRE-luciferase and TK-Renilla with or without increasing amounts of FLAG-Smad4 expression plasmid. After 24 h, cells were induced with the ligands shown and luciferase/Renilla assays were performed as described in the legend to Fig. 1. A Western blot assay showing the expression of FLAG-Smad4 in the MDA-MB-231 cells is shown. The asterisk denotes a nonspecific band.