Figure 3: SIRT3 negatively regulated osteoclast differentiation but not function.
From: Sirtuin 3 (SIRT3) maintains bone homeostasis by regulating AMPK-PGC-1β axis in mice
(a) BMMs were infected with retroviruses expressing HA-tagged SIRT3 or empty vector (EV). SIRT3 protein levels in whole cell lysates were detected by immunoblotting with anti-HA or anti-SIRT3 antibody. Actin serves as a loading control. (b) Osteoclast differentiation in BMMs infected with SIRT3 or EV. TRAP+MNCs (>3 nuclei) were counted. Scale bar, 500 μm. *P < 0.01. Data are represented as mean ± SD. (c,d) Expression of Nfatc1 and NFATc1-induced genes Atp6v0d2 during osteoclastogenesis. Infected BMMs were treated with RANKL for indicated days, and then subjected to qRT-PCR (c) or immunoblot analysis (d), respectively. Actin serves as a loading control. *P < 0.005 between the indicated groups. Data are represented as mean ± SD. (e) Bone resorption activity of WT or Sirt3−/− osteoclasts. After differentiation of BMMs into osteoclasts, cells were seeded onto dentine discs and further incubated with RANKL for 3 days. The cells were removed from the dentine discs and stained with hematoxylin for visualization of pit formation. The area of resorption pits were measured with Image-Pro Plus 4.5 (Media Cybernetics). Data are represented as mean ± SD. Scale bar, 100 μm. n.s., not significant.
