Figure 10 of
Wordinger, Mol Vis 2002;
Figure 10. Bone morphogenetic protein signaling pathway
Bone Morphogenetic Protein (BMP) dimers bind to a membrane complex composed of BMP receptors 1 and 2, which are serine/threonine kinases. The regulatory Smads (Smad1/Smad5) become phosphorylated and associate with a co-Smad (Smad 4). This resulting Smad complex enters the nucleus where is associates with transcription factors (TF) and regulates gene expression. BMP associated proteins act as BMP antagonists by binding BMPs and preventing BMP interaction with BMP receptors.