Fig. 2. Phenotypes associated with gbb clones in the posterior compartment. In all cases, the boundaries of the dorsal-ventral overlap of the clone are shown with broken lines. (A) A large gbb null clone in the posterior compartment shows loss of the PCV and the distal tip of L5, as seen in the gbb hypomorphs, but not the distal tip of L4. (B) A gbb null clone including half of the PCV and the L4/PCV junction. The PCV terminates within two to three cells inside of the clone boundary. (C) A gbb null clone mutant for the posterior half of the PCV and including the L5/PCV junction. In this case the PCV terminates two to three cells outside of the clone boundary. Note also that the proximal region of L5 is mutant and is truncated before reaching the margin, even though the tissue more distally is wild type for gbb function. (D) A gbb null clone that does not include the junctions between the PCV and L4 or L5. Although a significant part of the vein is mutant for gbb, the PCV is not interrupted. (E) Loss of gbb only affects the distal quarter of L5 even if more of the vein is covered in the clone (arrow, compare with Fig. 2A). In clones that cross L5 within this distal quarter (F), L5 is truncated at the clone boundary (arrow). (G) Clones that cover proximal L5 up to within the distal quarter truncate the vein as if all of L5 were mutant (vertical arrow), even if the distal most part of the wing is wild type for gbb. Note that this clone also truncates the PCV (horizontal arrow), but in this case, the vein terminates just outside the clone boundary.
