Figure 1. Ubx drives the expression of the DG3 shavenbaby enhancer along the ventral abdominal segments.
(A) The cis-regulatory region of the shavenbaby (svb) gene contains three enhancers expressing stripes on the ventral side of the abdominal segments: DG3, E3 and 7. (B) The expression patterns of the three enhancers are partially overlapping. The color scheme corresponds to (A), where DG3 is magenta, E3 is yellow and 7 is cyan. (C) Expression pattern of a reporter construct with the DG3 enhancer driving LacZ expression in an embryo with wild-type Ubx expression, as visualized using immunofluorescence staining. (D) DG3 reporter in Ubx null mutant shows no expression in A1 and significantly weakened expression in the other abdominal segments. (E) Overexpression of Ubx driven through a heat shock promoter induces overexpression of DG3 reporter in all abdominal segments and ectopic expression on the ventral surface of the thoracic segments T2 and T3.
Figure 1—figure supplement 1. Ubx enrichment around the three ventral svb enhancers.
