Genes Seen Turning Imaginal Fly Eyes Into Reality

Nashville, Tennessee—Deep within the larvae of most flies, beetles, moths, and butterflies lie quiescent but power-packed clusters of undifferentiated cells known as imaginal discs. In a process that researchers would dearly love to understand, the discs suddenly explode into life during metamorphosis: While the rest of the larva withers, they generate all the specialized cells that make up the adult insect's body. Now, after gazing deeply into developing fly eyes, researchers have gotten a better look at genes that make one imaginal structure real. At the national meeting of the Society for Developmental Biology here, scientists reported on four genes that help sweep a feature called the “morphogenetic furrow” across the eye imaginal discs of the fruit fly Drosophila melanogaster , transforming featureless cells into photoreceptors.