Fig. 3.

Nell-1^Wnt1KO newborn mice demonstrate defective osteochondrogenesis in CNCC-derived bones. a Cell lineage tracking in Nell-1^{Wnt1-tdTomato}KO mice clearly showed red fluorescence (yellow arrows) in the frontonasal bones (FB) and mandibular bones (MB) which are derived from Wnt1 expressing CNCC lineages; b, c More OCN positive cells were observed in the osteogenic front of the calvarial bone plate and mandibular bones in WT samples than in Nell-1^Wnt1KO samples. In contrast to OCN staining, TRAP positive staining showed a drastic increase in both the frontonasal and mandibular bones of Nell-1^Wnt1KO mice. The distinct correlation of OCN and TRAP staining in these bones was further revealed by quantitative analyses between WT and Nell-1^Wnt1KO mice; d The maturation of CNCC-derived cartilaginous tissues was severely inhibited in Nell-1^Wnt1-R26RKO mice with evidence of extremely low levels of Collagen type II matrix. *P < 0.05; **P < 0.01; ***P < 0.005; n = 3 for b–d