Bone morphogenetic protein 7

Overview
Bone morphogenetic protein 7 or BMP7 (also known as Osteogenic Protein-1 or OP-1) is a member of the TGF-β superfamily of proteins. Like other members of the bone morphogenetic protein family of proteins, it plays a key role in the transformation of mesenchymal cells into bone and cartilage. It is inhibited by noggin and a similar protein, chordin, which are expressed in the Spemann-Mangold Organizer. BMP7 may be involved in bone homeostasis. It is expressed in the brain, kidneys and bladder.

BMP7 induces the phosphorylation of SMAD1 and SMAD5, which in turn induce transcription of numerous osteogenic genes. It has been demonstrated that BMP7 treatment is sufficient to induce all of the genetic markers of osteoblast differentiation in many cell types.

Role of BMP7 in vertebrate development
BMP7 has been discovered to be crucial in the determination of ventral-dorsal organization in zebrafish. BMP7 causes the expression of ventral phenotypes while its complete inhibition creates a dorsal phenotype. Moreover, BMP7 is eventually partially "turned off" in embryonic development in order to create the dorsal parts of the organism.

In many early developmental experiments using zebrafish, scientists used caBMPR (constitutively active) and tBMP (truncated receptor) to determine the affect of BMP7 in embryogensis. They found that the constitutively active, which causes BMP to be expressed everywhere creates a ventralized phenotype, whereas truncated, dorsalized.

Recombinant human BMP-7 protein as a drug
BMP7 has Surgical uses and is marketed under the name brand name OP1 Sold by Stryker. It can be used to aid in the fusion of vertebral bodies to prevent neurologic trauma. Also in the treatment of tibial non-union, frequently in cases where an bone graft has failed.

BMP7 also has the potential for treatment of chronic kidney disease. Curis, Inc., reported in 2002 on the role BMP7 plays in the kidneys. In 2007 Johnson & Johnson returned its exclusive license for theurapeutic use of BMP-7 to Curis, with Curis being disappointed in the lack of development by J&J in ensuing time.