Fig. 5. Expression of Ihh and ColX in Ctgf mutants. (A-C) Expression of Ctgf (A), Ihh (B) and ColX (C) in the radius of an E14.5 wild-type embryo. The expression patterns of Ctgf and Ihh overlap in prehypertrophic and hypertrophic chondrocytes. Ctgf is co-expressed with ColX in hypertrophic chondrocytes at this stage and in prehypertrophic chondrocytes adjacent to the perichondirum (arrow in A). (D,E) Expression of Ihh (D) and ColX (E) in the radius of an E14.5 Ctgf mutant littermate. These markers are expressed in appropriate patterns in prehypertrophic and hypertrophic chondrocytes. Scale bar: 100 µm for A-E (F-H) Expression of Ctgf (F), Ihh (G) and ColX (I) in the radius of an E16.5 wild-type embryo. Ctgf is expressed primarily in hypertrophic chondrocytes in a pattern overlapping that of ColX, but transcripts also persist in chondrocytes adjacent to the perichondrium in the prehypertrophic zone (arrow in F). (I,J) Expression of Ihh (I) and ColX (J) in the radius of an E16.5 Ctgf mutant littermate. The domains of expression of Ihh are indistinguishable in wild-type and mutant littermates, indicating that the expansion of the hypertrophic zone revealed by histological analysis is not accompanied by an expanded prehypertrophic zone. Scale bar: 50 µm for F-J.