Fig. 5. pointed regulates the expression of hedgehog from an eye specific enhancer. (A-D) Third instar bar3:lacZ eye imaginal disc. The field shown is several columns posterior to the morphogenetic furrow, anterior towards the right. The disc contains a mosaic clone that is homozygous for the null mutation pnt^delta88. (A,D) GFP negatively marks the outlined clone. (B,D) Elav marks all the photoreceptors. (C,D) lacZ reporter. lacZ reporter expression is absent from within the pointed clone (a wild-type example outside the edge of the clone is indicated with a white arrow). The single R8 cells are Elav positive in the clone (black arrow). Scale bar: 5 µm.