Fig. 8

Loss of dorsal specification due to sqt morpholinos is rescued by the sqt 3′UTR. (A-H) Early gsc expression is not detected in sqtMO-injected (C), in contrast to ConMO-injected (A), zebrafish embryos. Expression of gsc is rescued in sqt morphants by co-injection of lacZ:sqt (E), but not with lacZ:glo (see supplementary material Fig. S4). Embryos co-injected with sqtMO and lacZ:sqt (F,I) or sqtMO and sqt^STOP:sqt (I) are rescued partially and are similar to MZsqt^cz35 mutant embryos (H). Images in F,H were acquired in different focal planes for the rostral and caudal regions of the embryo and subsequently assembled. (A,C,E,G) 30% epiboly, animal pole views with dorsal to the right; (B,D,F,H) prim-5 stage. Arrowheads (A,E) mark the extent of gsc expression. (I) Extent of rescue of sqtMO-injected embryos by co-injection of lacZ:sqt or sqt^STOP:sqt, versus control lacZ:glo RNA. Scale bars: 100 μm.