Fig. 5. Analysis of the collagen matrix in wild-type and mutant cartilage. (A,B) Electron micrographs of the pericellular and territorial (A) and the interterritorial (B) matrix compartments of wild-type and mutant growth plates at the newborn stage. Note the reduced collagen fibril density in the mutant compared to that in the wild type. (C,D) Immunohistochemical staining of the tibia for collagen type II (Col2) and type X (Col10) at the newborn stage. Collagen X was deposited in the hypertrophic (h) zone in both control and mutant mice. Note that the hypertrophic zone is smaller and that the collagen X staining extends deeper into the prehypertrophic/proliferative (p) zone in mutant cartilage. ec, epiphyseal cartilage. Bar, 400 nm (A and B); 100 µm (C and D).