There are at least 20 structurally and functionally related BMPs, which are members of the TGF-beta superfamily. BMPs were originally identified as protein regulators of cartilage and bone formation. They are also involved in embryogenesis and morphogenesis of various tissues and organs. BMPs regulate the growth, differentiation, chemotaxis and apoptosis of various cell types, including mesenchymal cells, epithelial cells, hematopoietic cells and neuronal cells. Similar to other TGF-beta family proteins, BMPs are highly conserved across animal species.
BMP4 is implicated in fibrodysplasia ossificans progressive. It is reported to be uniquely overexpressed in lymphoblastoid cells and preosseous fibroproliferative lesions. BMPs 1 to 6 are also reported to be expressed in prostatic adenocarcinomas with BMPs 1 to 5 also expressed in both benign and prostatic hyperplasia and ocular melanoma.
Smad1 translocation to the nucleus is observed after the addition of BMP4 (also designated BMP2B), suggesting that BMP4 may play a role in activation of the Smad pathway. BMP is secreted into the extracellular matrix.