Figure 4From: Key signaling nodes in mammary gland development and cancer: Smad signal integration in epithelial cell plasticitySchematic representation of Smad functions in the cell. The Smad complexes directly and indirectly control stimulus- and cell type-specific gene expression at multiple levels. EMT, epithelial-mesenchymal transition; Me, methyl group; TF, transcription factor; Ub, ubiquitin.Back to article page