FIGURE 1:

Cre-mediated replacement of Gja1. (A) Western blot analysis of whole-bone protein extracts from 3-mo-old mice showing strong expression of Cx43 in WTfl extracts and barely detectable immunoreactivity in cKO extracts. LacZ/Gja1 gene replacement was confirmed by the presence of β-gal immunoreactive bands only in cKO protein extracts. (B) β-gal-stained tibia sections of 1-mo-old mice showing specific β-gal staining present in the cKO but not the WTfl tibia sections. In the cKO bones, specific β-gal staining was observed in cells lining the endocortical surface, the periosteum, and in osteocytes (d’–arrows); however, very little β-gal staining was present in the trabeculae (e’), and none in the growth plate chondrocytes (f’). Comparative sections from 1-mo-old DM1;ROSA26 mice showing β-gal staining in cells lining the endocortical surface and osteocytes (g’), trabecular osteoblasts (h’), and growth plate chondrocytes (i’).