Fig. 10. Mirror-image duplication of gsc expression in the moz mutant second arch. Ventral (A-C,E,G) and lateral (D,F) views of gsc expression in whole-mount wild-type (A,D,E), moz mutants (B,F,G) and hoxa2b+hoxb2a-MO co-injected animals (C) at 33 hpf (A-C) and 41 hpf (D-G). In moz mutants and hoxa2b+hoxb2a-MO co-injected animals, second arch expression shift medially (arrows in B and C), mirroring the wild-type first arch pattern. (D-G) At 41 hpf in moz mutants, dorsal second arch gsc expression is reduced (arrowhead in F) and ventral expression is still inverted (arrows in E,G). (H) Schematic of expression domains visible in (A,B,E,G). In moz mutants, lateral second arch gsc expression is missing, and instead the second arch pattern resembles a mirror-image duplication of the first arch pattern, with a thin medial crescent of expression in the anterior medial arch. Relevant pharyngeal arches are numbered. e, eye. Scale bars: 50 µm.