Osteogenesis

 The first image is of a stained undecalcified section showing new bone formation induced by bone morphogenetic proteins (BMPs) in the baboon (Papio ursinus). Newly mineralized bone shows blue and osteoid red. The inset is a dark field image revealing in situ hybridization of osteogenic protein-1 (OP-1/BMP-7) mRNA transcripts expressed during embryo development. Multiple expression suggests multiple roles in embryonic development and postnatal regeneration.

We now understand that nature relies on common (and few) molecular mechanisms tailored to provide the emergence of specialized tissues and organs. The BMP/OP superfamily is indeed an elegant example of nature parsimony in programming multiple specialized functions deploying molecular isoforms with minor variation in amino acid motifs within highly conserved carboxy-terminal regions. Insights into the mechanisms of embryonic development is helping us to engineer skeletal regeneration and tissue morphogenesis in molecular terms.