Fig. 1

Fig. 1 Expression of radar during embryogenesis and its relationship to scl expression. (A) Dorsal posterior view of radar expression in a seven-somite-stage embryo (anterior to top). (Inset) Posterior optical cross-section (posterior down) displaying mesodermal radar expression as bilateral stripes in the lateral plate (arrows) relative to more dorsal ectodermal expression above the neural keel (arrowheads). (B) Dorsal posterior view of a double in situ hybridization staining for radar (purple; purple arrowheads) and scl (red; red arrowheads) in a seven-somite-stage embryo. (C) A higher power view of embryo in (B). (D) Diagrammatic representation (dorsal posterior view) of radar and scl expression in the lateral mesoderm of a seven-somite-stage embryo. (E) Expression of radar in the trunk of a 24-hpf embryo (anterior to left) and its cross-section (F). The hypochord (white arrowhead) and posterior endoderm (white arrow) express radar, as well as the developing dorsal fin (red arrow) and dorsal neural tube (red arrowhead). (G) Expression of radar in the tail of a 24-hpf embryo was detected in the posterior hypochord (black arrow) and ventral tail mesenchyme (black arrowhead). (H) Double in situ hybridization staining for radar (purple) and scl (red) in the tail of a 24-hpf embryo and its cross-section (I) displays an overlap of expression in the ventral tail mesenchyme (bracket in I). (J) Lateral view of radar expression (anterior to left) in the trunk of a 36-hpf-stage embryo. Black arrowhead in (I) denotes notochord and the blue arrow, the hypochord. YE, yolk extension; N, notochord; NT, neural tube; DA, dorsal aorta; PCV, posterior cardinal vein. Scale bars in (A–C), (E, G, H, J), and (I) represent 150, 100, and 50 μm, respectively.