Figure 5.

GMR-hid induces compensatory proliferation, and ark clones protect the newly formed cells from hid-induced apoptosis. (a) The suppressed eye of GMR-hid^w− is almost entirely composed of ark mutant tissue, phenotypically marked by absence of red eye pigment (white). Genotype: ey-FLP; FRT42D ark^G8/FRT42D P[w+]; GMR-hid^w−.(b) Adult eye of an ey-FLP-induced mosaic of ark^G8. The ark mutant tissue is marked by absence of red eye pigment (white); the twin spots (ts) and heterozygous cells are marked by red eye pigment. Genotype: ey-FLP; FRT42D ark^G8/FRT42D P[w⁺ ]. (c) Wild-type eye-antennal disc labeled for BrdU as proliferation marker. MF, morphogenetic furrow; SMW, second mitotic wave. (d) Wild-type eye-antennal disc labeled with anti-Hid antibody. (e) GMR-hid eye-antennal disc labeled with anti-Hid antibody. The bracket indicates the expression domain of GMR-driven hid expression posterior to the morphogenetic furrow. (f–h) GMR-hid eye-antennal disc labeled with BrdU (f) and anti-cleaved caspase-3 antibody (caspase-3*) (g). (h) is the overlay of (f) and (g). Arrows in (f) indicate the morphogenetic furrow (MF), the second mitotic wave (SMW) and the zone of compensatory proliferation (ZCP). The arrows in (g) indicate hid-induced cell death overlapping with the SMW and slightly posterior to the ZCP. (i–k) GMR-hid eye-antennal disc containing ey-FLP-induced ark clones labeled for BrdU (i) and anti-cleaved caspase-3 antibody (caspase-3*) (j). (k) is the overlay of (i) and (j). White lines in (j) and (k) mark ark clones. Genotype: GheF; FRT42D ark^G8/FRT42D P[w⁺]