Fig. 2. Eye development in the absence of sca or gp150, or both. Cells mutant for sca^OB7 are shown in A; cells mutant for gp150² are shown in B. Homozygous mutant cells were identified by lack of ß-galactosidase expression (magenta). R8 patterning is revealed by Senseless antibody staining (green). Separate Senseless and ß-galactosidase channels are shown in the middle and right columns, respectively, of each merged color image shown on the left. In the sca mutant clone (A), the spacing of Senseless-expressing cells was irregular and there were extra R8 cells. The gp150 mutant clone is similar (B). (C-F) Photoreceptor differentiation is shown by blue staining for ELAV antigen. In the wild-type (C) ommatidia are spaced regularly and each ommatidium consists of eight photoreceptor cells. (D) In gp150³/gp150⁴ spacing of the ommatidia was abnormal and some ommatidia had fewer or more photoreceptor cells (arrows). (E) sca^BP2 showed similar defects in slightly stronger form. (F) sca gp150 double mutants resemble sca. (G-J) SEM of adult eyes. (G) Wild type. (H) The gp150³/gp150⁴ mutant eye is rough. There are bigger or smaller ommatidia and extra bristles. (I) The sca^BP2 mutant eye also contains bigger or smaller ommatidia, and extra bristles. (J) sca^BP2 gp150³/gp150⁴ double mutant eyes resemble the sca single mutant.