Figure 7.

Expression of joint marker genes in the regenerating joints. In situ hybridization of Gdf5 (a joint cell marker) and Sox9 (a chondrocyte marker) and Alcian Blue/Nuclear Fast Red staining to serial sections close to each other in the regenerating spike at (A)−(C) 2 weeks, (D)−(F) 3 weeks, and (G)−(I) 4 weeks after the amputation. Arrowheads in each column indicate the signals for the Gdf5 and Sox9 expression and the signals for cartilage in Alcian Blue staining, respectively. Green arrowheads indicate the connecting part between the remaining articular cartilage and the regenerating spike cartilage at 3 weeks after the amputation.