Fig. 4. Rhombomere identity is not affected by the absence of Nkx6.1 activity. In situ hybridization on flat-mounted hindbrains at E10.5. The expression pattern of Hoxb1 (A,B), and Epha4 (C,D) is similar in wild-type (A,C) and Nkx6.1 mutant embryos (B,D).