neuralized is essential for a subset of Notch pathway-dependent cell fate decisions during Drosophila eye development

neuralized(neur) is a neurogenic mutant of Drosophila in which many signali ng events mediated by the Notch (N) receptor are disrupted. Here, we analyz e the role of neur during eye development. Neur is required in a cell-auton omous fashion to restrict R8 and other photoreceptor fates and is involved in lateral inhibition of interommatidial bristles but is not required for i nduction of the cone cell fate. The latter contrasts with the absolute requ irement for Suppressor of Hairless and the Enhancer of split-Complex for co ne cell induction. Using gain-of-function experiments, we further demonstra te that ectopic wild-type and truncated Neur proteins can interfere with mu ltiple N-controlled aspects of eye development, including both neur-depende nt and neur-independent processes.