Fig. 5. Levels of Egfr signalling are increased in ed mutants. (A-B') Confocal microscopy for immunohistochemical detection of Ato (green) and mAb323, which detects multiple E(spl) proteins (red), in third larval instar eye discs. (A,A') Wild type. (B,B') ed^4.12/ed^4.12. Levels of E(spl) are not altered in the mutant morphogenetic furrow (arrowhead). (C,D) Light microscope images of pnt-P1 mRNA in third larval instar eye discs. (C) Wild type, showing expression in the IGs. (D) ed^4.12/ed^4.12. pnt-P1 expression is greater in D. (E,F) Confocal microscopy for immunohistochemical detection of dp-Erk (green) and Ato (red) in third larval instar eye imaginal discs. (E) Wild type, showing expression in the IGs. (F) ed^4.12/ed^4.12. Levels of dpErk are higher in F.