Fig. 4.

Synergistic cell death of rbf stam double mutants is suppressed by expression of activated Ras, activated EGFR and secreted Spi but not by Rhomboid expression. (A–Gʹ) rbf stam (A–Dʹ,G,Gʹ) and rbf (E–Fʹ) MARCM clones are marked by GFP expression, and apoptotic cells are identified by Caspase-3 (C3) staining shown in red. Apoptosis in the morphogenetic furrow and posterior are indicated by blue and yellow arrows, respectively. (H) The levels of apoptosis in the indicated genotypes of rbf stam double-mutant MARCM clones located in the posterior of eye discs were quantified. The mean±s.d. are shown. The number of discs quantified for each genotype was: rbf stam¹⁹, n=8; rbf stam¹⁹ ras^v12, n=6; rbf stam¹⁹ EGFR^CA, n=6; rbf stam¹ sSpi, n=9; rbf stam¹⁹ rho, n=7. Asterisks indicate statistically significant difference (P<0.0001, Student's t-test) between triple- and double-mutant clones. Similar results were observed in three independent experiments. (I) A diagram that summarizes where stam mutation blocks EGFR signaling activation. The complete genotypes of the flies analyzed are detailed in Table S1. Scale bar: 100 µm.