9604865 Willis Metamorphosis endows many animals with the ability to occupy diverse niches within the life span of a single individual. Chemical disruption of metamorphosis has been a successful approach to pest control. It is known that two classes of hormones, juvenoids and ecdysteroids, regulate insect metamorphosis. Some limited information also exists about how gene expression changes during insect metamorphosis. Past work has focused on whole insects, isolated parts, and short term cultures of tissues derived from them. Despite elegant experiments by many workers, there is total ignorance of the mechanisms by which juvenoids control metamorphosis or even of the level at which gene expressions is regulated during metamorphosis. One of the most fascinating features of metamorphosis in advanced insects is that many pupal and adult structures arise from packets of seemingly undifferentiated cells, imaginal discs, that were set aside during embryonic or early larval life. Imaginal disc cells proliferate in larvae and evaginate and differentiate during an ecdysteroid-induced molt that is initiated in the absence of juvenoids This project is designed to learn if an established cell line (PID2A), derived from the wing imaginal discs of the Indian Meal Moth, Plodia interpunctella can serve as a simple model to study metamorphosis. The PI has already learned that these cells are responsive to ecdysteroids and that their response is blocked by juvenoids. Proposed work will focus on identifying proteins and gene transcripts that are differentially expressed following different hormone treatments. The treatments will be those that in the intact animal would either initiate or block metamorphosis. If the PI can show that some synthetic activities of these cells mimic those that occur n vivo, then a simple model system can be used to test hypotheses, factors, and genes that are being implicated in metamorphic regulation. ***
