MAP kinase-Gal4/Vp16 fusion protein expression suppresses the phenotype of a MAP kinase loss-of-function mutant. (A,B) Adult compound eyes. (C,D) Adult retinal tangential sections. (E,F) Forty-two-hour-old pupal retina stained for F-actin. (G,H) Third larval instar retina stained for F-actin. In all panels, anterior rightwards and dorsal is upwards. Genotypes as indicated. (Below) Histograms showing analysis of numbers of rhabdomeres per ommatidium in wild type, rl1 homozygotes and HS:MG rl1 double homozygotes. All animals were raised at 29°C.