Figure 7.

 Different amounts of Ubx protein cause different transformations. (A) Ventral aspect of a wild-type larva showing head, thorax, and the first three abdominal segments. The first abdominal segment (A1) has a characteristic thin belt of denticles, whereas those of more posterior abdominal segments are wider and with a trapezoidal shape. (B) Larva of genotype Gal4-444; UAS–Ubx, grown at 17°C, in which Ubx has been overexpressed during embryogenesis (see text). At this temperature the three thoracic and one head segments (*) are transformed toward A1, and the A1 segment remains unaltered. (C) Larva of the same genotype as B grown at 28°C. The greater amount of Ubx protein produces a transformation of A1, the three thoracic segments, and one head segment (*) into an A3–A5 segment type.