Fig. 3. A block of BMP signaling cannot overcome the Ihh-induced delay in hypertrophic differentiation. Forelimbs of E14.5 embryos from wild-type (A,B) or transgenic ColII/Ihh mice (C-F) were cultured for 4 days in control medium (A-D) or treated with Noggin protein (E,F). Serial sections of these limbs were hybridized with riboprobes for Ihh (A,C,E) or ColX (B,D,F). (A-D) Untreated limbs of ColII/Ihh embryos display a reduced expression domain of Ihh (C) and ColX (D), compared with untreated limbs of wild-type embryos (A,B). (E,F) Forelimbs of ColII/Ihh embryos treated with Noggin show a further reduction of Ihh (E) and ColX (F) expression. All panels show sections through the humerus.
