Characterization of the regulatory elements controlling neuronal expression of the A-isoform of the ecdysone receptor gene of Drosophila melanogaster

During the development of the adult central nervous system (CNS) of the fru itfly Drosophila melanogaster, the A isoform of the ecdysone receptor (EcR- A), a typical nuclear hormone receptor, is expressed at high levels in the Type II neurons, a set of neurons that die shortly after the emergence of t he adult. To understand the role that transcriptional regulation of nuclear receptor genes plays in CNS development, we have dissected the region cont rolling the transcription of EcR-A by analyzing the ability of this region to drive the expression of reporter genes in transgenic animals. These anal yses have demonstrated that the Type II neurons are a heterogeneous collect ion of neurons that utilize different regulatory elements to coordinate the expression of the same transcript. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.