Fig. 4. Non-autonomous rescue of puc expression in DME cells.

(A–D′) Stage 14 embryos stained for F-actin (red), Ush (green) and β-gal (blue). (A–A′) Wild type expression of the puc enhancer trap in the dorsal most row of epidermal cells. (B–B′) Puc reporter expression is abolished in ush² mutant embryos. Here, only one DME cell expresses β-gal. In this region of ush² mutant embryos remnant AS cells persist the longest before they degrade. (C–C′) β-gal expression is restored in DME of ush² mutant embryos where Ush function in the AS has been restored. Detection is only weaker in about 10 cells around the central region. (D–D′) Lower magnification of C shows β-gal is expressed along the entire leading edge. The scale bar in C applies to A and B.