DISTINCT MECHANISMS OF ACTION OF THE LOZENGE LOCUS IN DROSOPHILA EYE AND ANTENNAL DEVELOPMENT ARE SUGGESTED BY THE ANALYSIS OF DOMINANT ENHANCERS

The development of the olfactory sense organs on the antenna of the fr uit fly Drosophila utilises mechanisms distinct from those used in the rest of the adult peripheral nervous system, lozenge (lz) is the only locus hitherto identified as required for the development of antennal sense organs. In addition to effects on the antenna, mutations in It also affect the development of the eye and maxillary palp. We have use d the readily- scored eye-phenotype in a temperature sensitive It alle le to screen for dominant modifiers of phenotypes at this locus. We an alyse the phenotypes of both intragenic and extragenic modifiers. Our results reinforce the view from developmental studies that lz(+) funct ions in eye and antennal development in distinct ways.