Fig. 7 Barx1 positively influences cellular proliferation within the pharyngeal arches. (A, B) Sagittal serial sections (10 μm) of the pharyngeal arch region stained with Phosphohistone-H3 antibody. (A) Control embryo at 48 hpf. (B) barx1 morphant. The neural crest derived mesenchyme is overlaid in green; arrows indicate stained nuclei; e, eye; m, mandibular arch; h, hyoid arch; gill arches are numbered. Anterior is to the left. Scale bar: 50 μm. (C) Averaged cell proliferation in control uninjected embryos (black bars) and barx1 morphants (see Fig. 4; white bars) was determined within the mesenchyme as shown in panels A, B at the indicated four time points. Approximately fifty serial sections per embryo were examined. Number of embryos examined is indicated above each bar. Scale bar: (A, B) 50 μm.
Reprinted from Developmental Biology, 321(1), Sperber, S.M., and Dawid, I.B., barx1 is necessary for ectomesenchyme proliferation and osteochondroprogenitor condensation in the zebrafish pharyngeal arches, 101-110, Copyright (2008) with permission from Elsevier. Full text @ Dev. Biol.