six3 rescues chordin loss of function. (A-D) Lateral view of 24 hpf zebrafish embryos. Arrowheads indicate the eye/brain size in control (A), and in embryos injected with MoChd (B), six3 (C), or with both six3 and MoChd (D). Arrows indicate the posterior region, which is expanded in embryos injected with MoChd, or co-injected with MoChd and six3. (E-X) Early neurula embryos (90% epiboly) treated as in A-D and analysed for expression of the genes indicated. (E-P,U-X) Dorsal-anterior views, vegetal towards the bottom; (Q-T) lateral views, anterior towards the top.