|
Fig. 2 Barx1 expression. Embryos at (A, B) 13 hpf, (C)18 hpf, (D) 19 hpf, (E, F) 24 hpf, (G) 48 hpf, (H) 72 hpf, and (I) 96 hpf, were examined by in situ hybridization. (A) barx1 expression in the migrating neural crest in bilateral domains adjacent to the hindbrain (arrows). Anterior is at the top. (B) Coronal section through the hindbrain. (C) Lateral view of barx1 expression (arrow). (D) Double in situ of barx1 (dark blue, arrowhead) and crestin (red) co-expression in the neural crest streams indicated by Roman numerals. (E, F) Expression in the cranial neural crest streams. (G, G inset) barx1 expression in the pharyngeal arches and fin bud; a1, first arch; a2, second arch; d, dorsal expression domain; ga, gill arches; v, ventral expression domain; asterisk indicates the a2 intermediate region. (H) Lateral oblique view of barx1 expression in the chondrocytes. (I) Parasagittal section, open arrowhead indicates jaw joint. ch, ceratohyal; ceratobranchials are numbered; e, eye; fb, fin bud; g, gut primordium; hmc, hyomandibular condensation; M, Meckel's cartilage; ov, otic vesicle; pq, palatoquadrate; tr, trabecula. Scale bar: (B and I) 50 μm; (C, E–G) 100 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.