Fig. 4. Rescue of Xnr expression and normal development by injected Zic2 mRNA. (A) Expression of Xnr1, Xnr3 and Xnr5 in uninjected controls (Un), Zic2-depleted embryos and Zic2-depleted embryos (5 ng 10MP) injected with Zic2 mRNA (75 pg into oocytes prior to host transfer). Expression values are relative to the uninjected stage 10.25 sample. (B) Expression of Chordin, Gsc and Xhex in the same samples as A. (C) Examples of embryos from the experiment in A,B shown at two stages, late gastrula (stage 12, left panels) and tailbud (stage 36, right panels). (D) Expression of Xnr1 and Xnr5 in a second rescue experiment, as in A, except that 200 pg of Zic2 mRNA was used.