The sev promoter is fused upstream of sequence that encodes an activated form of Ras85D (amino acid 12 has been mutated to Val). Three copies of the sev enhancer are present downstream of the Ras85D coding sequence.
Rough eye phenotype, most ommatidia contain supernumerary R7 cells, aberrant packing and rotation of ommatidia, occasional extra or missing R1-R6 cells and missing pigment cells.