| First Author | Yu J | Year | 2021 |
| Journal | Int J Mol Sci | Volume | 22 |
| Issue | 4 | PubMed ID | 33672551 |
| Mgi Jnum | J:311648 | Mgi Id | MGI:6714580 |
| Doi | 10.3390/ijms22042097 | Citation | Yu J, et al. (2021) Pax5 Negatively Regulates Osteoclastogenesis through Downregulation of Blimp1. Int J Mol Sci 22(4) |
| abstractText | Paired box protein 5 (Pax5) is a crucial transcription factor responsible for B-cell lineage specification and commitment. In this study, we identified a negative role of Pax5 in osteoclastogenesis. The expression of Pax5 was time-dependently downregulated by receptor activator of nuclear factor kappa B (RANK) ligand (RANKL) stimulation in osteoclastogenesis. Osteoclast (OC) differentiation and bone resorption were inhibited (68.9% and 48% reductions, respectively) by forced expression of Pax5 in OC lineage cells. Pax5 led to the induction of antiosteoclastogenic factors through downregulation of B lymphocyte-induced maturation protein 1 (Blimp1). To examine the negative role of Pax5 in vivo, we generated Pax5 transgenic (Pax5(Tg)) mice expressing the human Pax5 transgene under the control of the tartrate-resistant acid phosphatase (TRAP) promoter, which is expressed mainly in OC lineage cells. OC differentiation and bone resorption were inhibited (54.2-76.9% and 24.0-26.2% reductions, respectively) in Pax5(Tg) mice, thereby contributing to the osteopetrotic-like bone phenotype characterized by increased bone mineral density (13.0-13.6% higher), trabecular bone volume fraction (32.5-38.1% higher), trabecular thickness (8.4-9.0% higher), and trabecular number (25.5-26.7% higher) and decreased trabecular spacing (9.3-10.4% lower) compared to wild-type control mice. Furthermore, the number of OCs was decreased (48.8-65.3% reduction) in Pax5(Tg) mice. These findings indicate that Pax5 plays a negative role in OC lineage specification and commitment through Blimp1 downregulation. Thus, our data suggest that the Pax5-Blimp1 axis is crucial for the regulation of RANKL-induced osteoclastogenesis. |
