Open AccessDual Requirement for the EcR/USP Nuclear Receptor and the dGATAb Factor in an Ecdysone Response in Drosophila melanogaster
Author(s) -
Véronique Brodu,
Bruno Mugat,
JeanYves Roignant,
JeanAntoine Lepesant,
Christophe Antoniewski
Publication year - 1999
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.19.8.5732
Subject(s) - ecdysone receptor , ecdysone , biology , enhancer , nuclear receptor , drosophila melanogaster , transcription factor , microbiology and biotechnology , hormone response element , hormone , gene , genetics , endocrinology , estrogen receptor , cancer , breast cancer
The EcR/USP nuclear receptor controls Drosophila metamorphosis by activating complex cascades of gene transcription in response to pulses of the steroid hormone ecdysone at the end of larval development. Ecdysone release provides a ubiquitous signal for the activation of the receptor, but a number of its target genes are induced in a tissue- and stage-specific manner. Little is known about the molecular mechanisms involved in this developmental modulation of the EcR/USP-mediated pathway. Fbp1 is a good model of primary ecdysone response gene expressed in the fat body for addressing this question. We show here that the dGATAb factor binds to three target sites flanking an EcR/USP binding site in a 70-bp enhancer that controls the tissue and stage specificity of Fbp1 transcription. We demonstrate that one of these sites and proper expression of dGATAb are required for specific activation of the enhancer in the fat body. In addition, we provide further evidence that EcR/USP plays an essential role as a hormonal timer. Our study provides a striking example of the integration of molecular pathways at the level of a tissue-specific hormone response unit.