Figure 4  Chondrogenesis Starts and Proceeds Normally Even in the Absence of BMP2 and BMP4
(A and B) Whole mount skeletons from E13.5 embryos that are stained with alcian blue. (A) Wild-type embryo, (B) Bmp2C/C; Bmp4C/C; Prx1::cre embryo. Black arrow in (B) shows the fusion of the zeugopod and stylopod.
(C and D) Hematoxylin and eosin–stained sagittal sections of humeri from E13.5 wild-type (C) and Bmp2C/C; Bmp4C/C; Prx1::cre (D) embryos. Thick red arrow in (C) shows the hypertrophic region.
(E and F) Sagittal sections of wild-type (E) and Bmp2C/C; Bmp4C/C; Prx1::cre (F) humeri from E15.5 embryos were hybridized with digoxigenin-labeled antisense rioprobes for ColX.
(G and H) Sagittal sections of forelimbs from E13.5 wild-type and BMP2, BMP4–deficient embryos, respectively, stained with radioactive riboprobes for Bmp7 mRNA. (G′) and (H′) show the bright field views of (G) and (H), respectively.