Fig. 4

Fig. 4

miR-27 is required for differentiation of pre-chondrogenic crest (PCC) cells in pharyngeal arches. (A) Expression of the chondrogenic marker sox9a, the osteogenic marker, runx2b, and the chondrocyte-specific marker col2a1a in MO-ctl or MO-27 (5 ng) injected embryos, detected by whole-mount in situ hybridization. Arrowheads indicate the expression domain of the ceratobranchial arches. All panels except the top panel for col2a1a are lateral views. Top panel for col2a1a expression is a ventral view with the first pharyngeal arch indicated by an arrowhead. (B) Anti-Col2 and anti-GFP immunostaining in the pharyngeal arch region between the eye and otic vesicle (ov) in Tg(fli1a:eGFP)y1 embryos at 61hpf. A single optical section of the confocal stacks is shown in each image, with anterior to the left. Embryos were injected with the corresponding morpholinos as described above. (C) Wheat-germ agglutininstaining and anti-GFP immunostaining in the pharyngeal arch region between the eye and otic vesicle (ov) in Tg(fli1a:eGFP)y1 embryos at 61hpf. The indicated ratio represents the number of embryos with the represented phenotype/total number of observed embryos. Scale bar, 50 µm.