Twenty Drosophila visual system cDNA clones: one is a homolog of human arrestin

From a group of 436 Drosophila melanogaster cDNA clones, we selected 39 that are expressed exclusively or predominantly in the adult visual system. By sequence analysis, 20 of the clones appear to represent previously unreported distinct cDNAs. The corresponding transcripts are detected in the retina and optic lobes. The genes are scattered throughout the genome, some near mutations known to affect eye function. One of these clones has been identified, by sequence analysis, as the structural gene (Arr) for a Drosophila homolog of human arrestin. Vertebrate arrestin interacts with rhodopsin in phototransduction and has been associated with an autoimmune form of uveitis in primates. The presence of an arrestin homolog in Drosophila suggests that both the vertebrate and invertebrate phototransduction cascades are regulated in a similar manner.