Impaired bone development and increased mesenchymal progenitor cells in calvaria of RB1-/- mice.

ABSTRACT: We have previously shown that the retinoblastoma protein (pRb) can activate expression of Runx2-dependent, bone-specific genes in cultured cells. We now show that pRb also plays a role early in osteogenesis, and that in primary RB1(-/-) calvarial cells there is an increased osteoprogenitor pool. To understand pRb's function in vivo, we generated a conditional RB1-KO mouse in which pRb expression is efficiently extinguished in osteoblasts. These animals display an apparent developmental defect in bones, most strikingly in the calvaria. Cultured RB1(-/-) calvarial osteoblasts fail to cease proliferation upon reaching confluence or following differentiation. Re-plating assays of primary RB1(-/-) calvarial cells after differentiation showed a clear adipogenic ability with increased multipotenc

SUBMITTER: Gutierrez GM 

PROVIDER: S-EPMC2585042 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature