Lineage commitment of mesenchymal progenitor cells is still poorly understood. Here we
demonstrate that Wnt signaling by osteoblasts is essential for mesenchymal progenitor cells
to differentiate away from a default adipogenic into an osteoblastic lineage. Dominant
adipogenesis and reduced osteoblastogenesis were observed in calvarial cell cultures from
transgenic mice characterized by osteoblast-targeted disruption of glucocorticoid signaling.
This phenotypic shift in mesenchymal progenitor cell commitment was associated with …