Expression of Xpax2 (A–C, J, and K), Xvax2 (D–F), and Xvent2 (G–I) genes in tail-bud (A–I) and tadpole (J and K) embryos injected with VAX2 RNA unilaterally. (A, D, and G) st. 23 injected embryos, frontal view. On the injected side (right), the Xpax2 and Xvax2 expression domains, normally confined to the ventral developing eye, are expanded dorsally (A and D), whereas the Xvent2 expression, which is dorsal in the control side, is strongly reduced (G). (B, E, and H) st. 23 injected embryos laterally viewed from the injected side. (C, F, and I) The same embryos shown in B, E, and H laterally viewed from the control side. (J and K) st. 33 injected embryos, laterally viewed from the injected (J) or the control (K) side. On the control side, Xpax2 expression in the optic cup is exclusively restricted to the lips of the optic fissure (arrowhead in K), whereas, on the injected side, Xpax2 expression expands both in ventral and anterodorsal regions of the eye cup (arrowheads in J).