The nervous system of multicellular organisms is a complex network of diverse cell types with unique positions and patterns of connectivity. Understanding how these cellular phenotypes develop from these intricate patterns is a central problem in cell and developmental biology. The Drosophila compound eye is well suited for studying these processes. The research is aimed at understanding the cellular interactions involved in pattern formation in the developing eye, specifically the role of photoreceptor cell R8 which is thought to play a central role in these events. The investigators have recently identified a new genetic locus rap (retina aberrant in pattern) whose functions are critical for pattern formation in eye. Studies with a temperature sensitive mutant have shown that rap function is essential during pattern formation and preliminary immunocytological studies indicate that rap gene function is involved in early events during pattern formation. In addition, genetic mosaic studies show that rap gene function is required only in the photoreceptor cell R8 for normal eye pattern formation. The research is aimed at a genetic and molecular analysis of the rap gene with a view to understanding the molecular nature of the rap gene product and its expression patterns. Furthermore, the genetic interactions that are important for rap function will be identified. These studies will facilitate an understanding of the nature of cellular interactions underlying neural pattern formation.
