Fig. 1.

Tamoxifen induces efficient chondrocyte-specific gene deletion in Col2a1-CreER^T2; R26R^+/− and Col2a1-CreER^T2; Tak1^f/f mice. (A) β-galactosidase staining of knee joint sections from Col2a1-CreER^T2; ROSA26R (Cre⁺; R26R) mice and Cre-negative control littermates (R26R) injected with tamoxifen (100 mg/kg body weight, intraperitoneally) three times, every other day, beginning at 1 week of age. The mice were killed at 1 (top two panels) or 3 (bottom two panels) months of age. (B) TAK1 immunohistochemistry of knee joint sections from Col2a1-CreER^T2; Tak1^f/f (Cre⁺; Tak1^f/f) mice and Cre-negative control littermates (Tak1^f/f) injected with tamoxifen as described above and sacrificed at 1 month of age. AC, articular cartilage; GP, growth plate cartilage.