Fig. 2
Ablation of Col2+ cells causes lethality in newborn mice due to the absence of endochondral bone and cartilage. a Gross appearance of Col2-cre and Col2-cre;DTA+/− mice at P0. The mutant mouse is small and has an extremely short four-limb pattern. b X-ray of P0 wild-type and mutant embryos. c Skeletons of Col2-cre and Col2-cre;DTA+/− mice at E17.5 and the newborn stage. Embryos and newborns were double stained with Alizarin red/Alcian blue. d Alizarin red/Alcian blue staining of skulls of Col2-cre and Col2-cre;DTA+/− newborns. Red arrow, complete loss of cartilage in Col2-cre;DTA+/− mice. e Alizarin red/Alcian blue staining of the mandibles of Col2-cre and Col2-cre;DTA+/− newborn mice. f Interior view showing the lack of mandibles in the skulls of Col2-cre and Col2-cre;DTA+/− newborn mice. Red arrow, bone loss in Col2-cre;DTA+/− mice. g Hindlimbs of Col2-cre and Col2-cre;DTA+/− newborn mice. Red arrow, bone loss in Col2-cre;DTA+/− mice. h Ribs of Col2-cre and Col2-cre;DTA+/− newborn mice. Red arrow, bone loss in Col2-cre;DTA+/− mice. i Clavicles of Col2-cre and Col2-cre;DTA+/− newborn mice. Red arrow, partial clavicle loss in Col2-cre;DTA+/− mice. n = 6 mice per condition; three independent experiments
