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Figure 6
Expression of the Xrx1 (A–C) and Xpax2 (D–F) genes in tadpole embryos injected with VAX2 RNA unilaterally, as detected in sections after whole-mount in situ hybridization. Transversal (A and D) and frontal (B and E) sections of st. 33 injected embryos, cut at the level of the optic stalk. Both the morphology and Xpax2 expression indicate the presence of an enlarged optic stalk on the injected side (arrowhead). The extent of the Xrx1 expression domain is similar in both the injected (right) and control (left) sides. Remarkably, dorsal expansion of Xpax2 expression is detectable in the retinal tissue contiguous with the enlarged optic stalk (D). (C and D) Transversal sections of st. 33 injected embryos, cut at the level of the lens. (C) On the injected side (right), surrounding of the lens by the optic cup is abnormally ventral (arrow); the Xrx1 RNA distribution is more uniform along the ventrodorsal axis compared to the control side. (F) Ectopic Xpax2 transcription is evident in the ventral retina of the injected side (right). |
