Function of the bone protein osteocalcin: definitive evidence

Mice that lacked the genes for the bone protein osteocalcin were generated and were used to study the function of osteocalcin. These osteocalcin-deficient mutants had normal bones at birth but had increased bone density and thickness at 6 months. Their osteoblasts deposited more bone matrix than those of wild-type mice, though mineralization was not affected. Osteocalcin, therefore, was concluded to be a negative regulator of bone formation.