Fig. 3. fas3 and coracle are potential targets of Grh. (A,B) Levels of Fas3 (FasIII; red, A,B; white, A',B') and Coracle (blue, A,B; white, A'', B''') are subtly reduced in grh-mutant clones (identified by absence of GFP, green, in A,B). Clone boundaries are indicated by arrows. (C) Grh binds to sites from fas3 and coracle genes. Amount of Grh complexed with labelled Gbe2-binding sites in the absence (O) or presence of the indicated competitors (5x molar excess and 50x molar excess). N-box is an unrelated E(spl) target site. Lane 1 has no added protein; all other lanes contain GST-Grh bacterial extract. (D) Fold stimulation by Grh of luciferase reporter genes containing fragments spanning the indicated sites. 4xGbe, positive control with oligomerised Gbe2 sites; hid1, negative control. (E) Rhodamine-conjugated dextran is excluded from the tracheal lumen (arrows) of wild-type (wt) and grh-mutant (grh^B32/grh^B32) embryos but not from SJ mutants (Atp; SJ^–).