Fig. 2

Atoh8 is absent in embryonic bone osteoblasts but expressed in prehypertrophic chondrocytes, and it is detected in osteoblasts of adult bone. a ISH analysis of the mouse E17.5 humerus with the Atoh8 probe. A DapB probe served as a negative control. Brown positive signals of Atoh8 were evident in muscle (arrowhead) but absent in bone osteoblasts (asterisk). Scale bar = 100 μm (left panels) and 50 μm (right panels). b ISH analysis of the mouse E17.5 humerus with the Atoh8 probe. Red positive signals of Atoh8 were detected in prehypertrophic chondrocytes (arrowhead) but absent in bone osteoblasts (asterisk). Scale bar = 100 μm (left panel) and 50 μm (right panel). c ISH analysis of the tibiae of 8-week-old mice with the Atoh8 probe. A Ppib or a DapB probe served as the positive or a negative control, respectively (Fig. S1). Red positive signals of Atoh8 were evident in bone-lining osteoblasts (arrowheads) and clusters of stromal cells (open arrowheads) but absent in bone-embedded osteocytes (asterisks). WT wild type; KO knockout. Scale bar = 50 μm. d mRNA was purified from the indicated tissues collected from 8-week-old wild-type mice and subjected to RT-qPCR analysis of Atoh8. Values were normalized to Gapdh expression (n = 5). Data are shown as the mean of log₂ value ± SD. *P < 0.05