Figure 1.

SMAD3 interacts with NKX2.1 (Panel A) and both FOXA1 and FOXA2 (Panel B) in lung epithelial cells. Mammalian two-hybrid assays were performed in A549 cells using Vp16-Nkx2.1, Vp16-Foxa1 or Vp16-Foxa2 expression plasmids according to the protocol described in Materials and Methods section. Luciferase readings from the controls consisting of, empty Vp16 and Gal4 plasmids alone, or in combination with Vp16-Nkx2.1, Vp16-Foxa1 or Vp16-Foxa2 were adjusted to unity and used to normalize all experimental results. Representative results from three independent experiments are shown. Asterisks denote P < 0.05.