DESCRIPTION (Verbatim from the applicant's abstract): The goal of this proposal is to study the genetic and molecular mechanisms of programmed cell death using the Drosophila eye as a model system. Although the basic machinery of programmed cell death has been characterized, few molecules involved in the signaling or initiation have been found. Our laboratory has performed a genetic screen for just such molecules. Studying programmed cell death in this genetic and easily analyzed system may lead to the discovery and characterization of the molecules involved in initiating or triggering programmed cell death as well as new molecules involved in the cell death machinery. This goal of this work is to complete the basic analysis and mapping of mutations isolated in the cell death screen and to molecularly and genetically characterize at least one of these, INXS, in detail.