Panx3 promotes the growth of metatarsus ex vivo. (A) Live images of ex vivo metatarsal growth (top) and histology (bottom). (a) Newborn mouse metatarsal bones were cultured and infected with Panx3 adenovirus (AdPanx3) or control adenovirus. (b) Metatarsus cultures were incubated with the Panx3 peptide for 3 d. Metatarsal bone growth was measured by real-time imaging. AdPanx3 promoted metatarsal bone growth (a), whereas the Panx3 peptide inhibited it (b). (B) Relative change in metatarsal length (Ba) or width (Bb) after 3 d in culture compared with day 0. The bone length was measured from edge to edge (A, a, broken red line). The width was measured from side to side (A, a, red line). AdPanx3 promoted the growth of both length and width, whereas Panx3 peptide inhibited both. (C) Quantitative RT-PCR. Metatarsus cultures were incubated for 3 d with AdPanx3 or the Panx3 peptide. AdPanx3 promoted the expression of osteoblast marker genes, osterix, ALP, and Ocn. The Panx3 peptide inhibited this marker gene expression. *, P < 0.05; **, P < 0.01. Error bars represent the mean ± SD; n = 3.