Fig. 8

Depletion of raraa or rarab alters sensitivity to exogenous RA. Confocal images of RARE-YFP transgenics at 20 hpf. Dorsal views, anterior to the left. (A) Controls express YFP up to an anterior border between r6 and r7 in the hindbrain (adjacent to somite 1), and in the anterior spinal cord. (B) YFP expression is lost in embryos treated with 1 μM DEAB, and reduced/shifted posteriorly at lower DEAB concentrations (C, D). (E–H) raraa morphants. Untreated morphants express YFP similar to controls (E), and lack expression when treated with 1 μM DEAB (F), but show little change in expression at lower DEAB concentrations (G, H). (I–L) rarab morphants show reduced YFP expression that shifts posteriorly (I), lack expression when treated with 1 μM DEAB (J) and show stronger reduction/shifts in expression when treated with lower DEAB concentrations than controls (K, L). (M–P) raraa/rarab double morphants also show reduced/shifted YFP expression (M), and almost completely lose expression when treated with 0.1 μM DEAB (O). Abbreviations: o, otic vesicle; s1, somite #1.