Analysis of cranial NCC migration in mCOUP-TFI mutants. Wild-type (A–C) or mutant embryos (D–F) were hybridized with CRABP I antisense probe to examine the migration of the neural crest cells. Whole-mount in situ hybridization on E9.0 (A,D) and E9.5 (B,E) embryos. (C,F) in situ hybridization with CRABP I antisense probe on sections of late E9.5 embryos. (c9–c10) Neural crest cells for ganglia IX and X; (fn) frontal nasal mesenchyme; (r) rhombomere; (r2c, r4c, r6c) neural crest cells from r2, r4, r6, respectively; (ot) otic vesicle; (4, 5, and 6) r4, r5, and r6, respectively.