Figure 9.

Homology between Smad3 and other members of the Smad family in the transcriptionally active 200–253 region. The amino acid identity among Smad family members is shown by gray shadowing. The single letter code for the representation of the amino acid sequences was utilized. The thin black arrow indicates the internal deletion that was introduced into full-length Smad3 protein. The wide white arrows represent β strands. A missense mutation in a conserved amino acid present in the β1-strand of Smad4 (E330), which is associated with tumors, is shown with an asterisk. Ser-Pro motifs that are potential targets for phosphorylation by MAP kinases in Smad3 are shown by open squares.