Tumor necrosis factor (TNF) plays an important role in the pathogenesis of inflammatory
bone loss through stimulation of osteoclastic bone resorption and inhibition of osteoblastic
bone formation. Compared with the well established role of TNF in osteoclastogenesis,
mechanisms by which TNF inhibits osteoblast function have not been fully determined.
Runx2 is an osteoblast-specific transcription factor whose steady-state protein levels are
regulated by proteasomal degradation, mediated by the E3 ubiquitin ligases, Smurf1 and …