Fig. 6. Complementary expression of Fez/Fezl and Irx1. (A-D) Expression of Fez (A,D), Fezl (B) and Irx1 (C,D) at E8.5. (D) Two-color staining. Fez and Irx1 transcripts were stained with BM Purple and Fast Red; the fluorescence image from the Fast Red was superimposed on the bright-field image. (E-M) Expression of Fez (E), Fezl (F) and Irx1 (G) at E9.5. (H-M) Sagittal sections of E9.5 embryos were hybridized with Fez and Irx1 (H-J), or Fezl and Irx1 probes (K-M). The hybridized signals were stained with BM Purple (Fez and Fezl) and Fluorescein (Irx1). Bright-field images (H,K), fluorescence images (I,L) and the bright-field and fluorescence superimposed images (J,M).