Lrp5 acts in the late stages of osteoblast differentiation.

<p>(A) Lrp5 mRNA levels in primary calvarial osteoblasts were assessed by qPCR during 14 days of osteogenic differentiation. (B) Lrp5 and Lrp6 mRNA levels were assessed by qPCR in calvarial osteoblasts isolated from Lrp5 floxed mice and infected with adenovirus expressing GFP (control) or Cre recombinase. (C) Axin2 mRNA levels were examined in control and ΔLrp5 osteoblasts in cells treated with 100 ng/ml Wnt-3a. (D) Cell proliferation was assessed by BrdU incorporation. Osteogenic (E) and osteoclastogenic markers (F) were examined by qPCR after 14 days of differentiation in osteogenic media. (G) Mineralized nodule formation was assessed by staining for alkaline phosphatase (AP), von Kossa (VK) and Alizarin red (ARS) after 14 days of differentiation. *p<0.05.