| |
Id3 depletion results in a loss of neural crest derivatives. (A) Dorsal (panel a) and ventral (panel b) views of an embryo injected with control-MO showing symmetrical head morphology. Dorsal (panel c) and ventral (panel d) views of an embryo injected with Id3-MO exhibiting structural loss on the injected side (arrow). The arrowhead indicates the midline. (B, panel a) Schematic diagram of cartilages in a stage 45 embryo. The different colors indicate the skeletal elements originate from different streams of migrating cranial neural crest. Meckel's (i), cerathoyal (ii), basihyal (iii), and branchial arch (iv) cartilages are shown here. (Panel b) Cartilage staining of a control embryo shows the symmetrical structures shown in the diagram. (Panels c,d) Whole or partial loss of cartilage on the Id3-MO-injected side. The dotted red line indicates the midline. (C) The dorsal fin of a control-MO-injected embryo is intact (panel a), but an Id3-MO-injected embryo exhibits a collapsed dorsal fin by depletion of the structure on the injected side (panel b). (D) Anterior and posterior patterning in Id3-MO-injected embryos is normal (panel b) compared with the control (panel a). (E) Stage 31 embryo injected with Id3-MO and subjected to in situ hybridization with a trp-2 probe. (Panels a,b) Eyes express trp-2. trp-2-positive pigment cells (purple) that are newly synthesized (dorsal neural tube; white arrow) or migrating superficially under the ectoderm (lateral; black arrowhead) are depleted or decreased on the Id3-MO-injected side (panels a,c), compared with the control side (panels b,d). (Panels a,c) Red dots (red arrow) are Red-Gal staining indicating Id3-MO-injected cells. (F) sox10 expression is lost in migrating neural crest cells destined to give rise to cranial ganglia (V, VII, IX, and X) on the Id3-MO-injected side that is marked by Red-Gal staining (panel a), compared with the control side (panel b). |
