Fig. 2. Expression domains of skeletogenic markers in the developing dentary bone. (A-J) HH39 chick embryos; (K-O) 16.5 dpc mouse embryos. Expression of Coll II (A) and Coll IX (B) is detected in cells of both Meckel's cartilage and dentary bone. (C) Expression of Sox9 can be seen in cells of Meckel's cartilage but not in the dentary bone. (D) Expression of Runx2 is limited to the cells of the dentary bone. (E) Osteopontin is expressed in cells of dentary bone but is restricted to the more mature cells. (F) Bmp2,(G) Bmp4, (H) Ihh and (I) strong expression of PTHrP-R are detected in the dentary bone. (J) H&E staining of the dentary bone and Meckel's cartilage from the embryo in A-I. In mice, (K) Coll II, (L) Runx2 and (M) Osx are expressed in the peripheral cells, whereas (N) the more mature osteoblast marker Opn is expressed in cells surrounded by mineralized matrix (H&E stain; O). dnt, dentary bone; MC, Meckel's cartilage. Scale bars: 200 µm.