Fig. 1. Transgenic Xenopus laevis embryos at different stages carrying Xrx1A-GFP construct 1 (A,D,G,J; see Fig. 3), displaying GFP fluorescence (B,E,H,K). (C,F,I,L) In situ hybridization of Xrx1A probe to non-transgenic embryos of the same developmental stage to demonstrate the normal expression pattern of the Xrx1A gene. A-C, stage 15; D-F, stage 21 (frontal view); G-I, stage 21 (side view); and J-L, stage 28.