Figure 3. Transgressions of the A/P and the D/V border caused by ablation of the P or the D compartment.

(A and B) Wing discs after 48 hr of Hid treatment followed by 72 hr of recovery. The original Hh lineage is labeled by ßgal (green), the A compartment is marked with an anti-Ci antibody (red) and the nuclei with Topro (blue). (A) Note the presence of groups of cells (asterisk) originated in the anterior compartment (they lack the βgal label) but that have lost Ci activity, indicating that they have lost anterior identity. (B) The unexpected finding that cells from the P compartment–they are part of the Hh lineage–can penetrate in the A compartment and to acquire anterior identity, as demonstrated by the Ci marker (arrows) (C) Portion of a disc in which the P compartment has been ablated, containing two sets of ‘twin’ clones labeled with GFP-green/LacZ ßgal (see ‘Materials and methods’ for details). The clones were initiated at the beginning of the ablation of the P compartment and fixed 24 hr after the end of ablation. In those panels the A/P borderline is blue and the twin clones delineated in red or green. Note that the two cases the clones cross over the A/P line. (D) Wing disc after 48 hr of Hid induction in the dorsal compartment followed by 72 additional hours of recovery. Note the presence of groups of cells (asterisks) that in spite of their ventral origin (lack of dorsal lineage βgal label) now present dorsal markers as the mew Integrin (PS1α). See also Figure 3—figure supplements 1 and 2.

DOI: http://dx.doi.org/10.7554/eLife.01831.006

Figure 3—figure supplement 1. Transgressions detected during the ablation period and transgressions using p53 as apoptotic inducer.

(A) Wing disc fixed at the end of 48 hours hid induction. Note that the trespassing cells (with lack of βgal label, indicated by an asterisk), have activity of the posterior marker engrailed. (B) Wing disc after 48 hr of p53 over-expression in the posterior compartment and 72 additional hours of recovery. Note the presence of compartment transgressions (red arrows, cells that lack the βgal label). Occasionally, part of the cells of a transgression retain its original identity, as the example pointed with a white arrow, in which a group of Ci positive cells remain trapped in the posterior compartment.

DOI: http://dx.doi.org/10.7554/eLife.01831.007

Figure 3—figure supplement 2. Localization on the wing disc of the different transgressions of the A/P border.

We have plotted all the transgressions found in after overexpressing the pro-apoptotic gene hid a disc containing the normal doses of Polycomb (A) or only one dose (B). The transgressions from A to P are in light blue and the P to A in light red. The darker color indicates the superimposition of several transgressions in some regions. Note that virtually all the transgressions reach the A/P border. Those from A to P exhibit some preference for the region between hinge and pouch, whereas those from P to A localize to the wing pouch. The overall preferential location of the transgressions near the A/P border rules out the possibility of incomplete label of the hh lineage.

DOI: http://dx.doi.org/10.7554/eLife.01831.008