Genes with significantly decreased (A) or increased (B) expression in mutant (Mox2Cre;Gmnnflox/flox) versus wt embryos were defined by microarray analysis of trunk paraxial tissue. (C,D) Top GO terms were defined using Metacore Suite/GeneGo for these data sets. (E,F) Neurofilament immunostaining of wt (E) or mutant (F) embryos. (E′,F′) boxed regions from (E,F). For several somites, white arrows highlight neurofilament staining and black arrowheads denote somite boundaries. In the mutant, staining for neural crest is normal in the rostral trunk, but differentiated neural crest is absent in the caudal region of the trunk.