Fig. 2

(A) Confocal projections of dissected Ch bones at five successive stages. Merged fluorescent and brightfield channels show the gradual replacement of the cartilage with a fat-filled core. col2a1a:mCherry-NTR highlights chondrocytes that become increasingly restricted to two growth plates (GP) at either end of the bone. fli1a:GFP labels endothelial cells and chondrocytes located in the central portions of the growth plates. Vascularization of the Ch increases over time. n = 2 at each stage. (B) Confocal projection shows networks of kdrl:GFP+ vascular endothelial and lyve1:DsRed+ lymphatic endothelial cells within an adult Ch bone. The inset shows a single confocal section through the boxed portion of the growth plate, with both blood and lymphatic vessels abutting the edges but not penetrating into the growth plate. n = 2. Scale bars = 100 μm (A) and 200 μm (B).