Expression is first observed in the R8 cell of a few ommatidia starting at row 8 after the morphogenetic furrow, and 1-2 rows after that, in all ommatidia to the posterior end of the larval eye imaginal disc. It is also observed in a subtype of glial cells in the eye disc. Expression is observed in R8 cells in the pupal stage, not including the dorsal rim area. No expression is observed in the retina in adults but a subset of glia are labelled in the lamina.