Fig. 5. ptc expression is enhanced by Sxl. Discs stained for ß-gal which reports ptc transcription from a ptc-lacZ transgene. (A) Wild type, (B-E) discs expressing Sxl in dorsal compartment by ap-GAL4 driver; (B,D) male, (C,E) female. In both sexes, ptc expression is more intense in the dorsal compartment (arrowhead marks dorsoventral boundary at the AP boundary for all panels). Arrow in B indicates broadening of ptc-lacZ zone and beginning of wing pouch expansion in dorsal half; in D, the fold from overgrowth is larger and the ptc-lacZ forms a U (arrow). The width of ptc-lacZ expression narrows in females (C), more so in E (which also has a larger dorsal half). Normal width of ptc-lacZ in E indicated by arrows. Scale bars: 20 µm. Anterior is towards the left, ventral is towards the top. Confocal images throughout.