The DHR3 orphan receptor gene is induced directly by the steroid hormone ecdysone at the onset of Drosophila metamorphosis. DHR3 expression peaks in early prepupae, as the early puff genes are repressed and betaFTZ-F1 is induced. Here we provide evidence that DHR3 directly contributes to both of these regulatory responses. DHR3 protein is bound to many ecdysone-induced puffs in the polytene chromosomes, including the early puffs that encode the BR-C and E74 regulatory genes, as well as the E75, E78 and betaFTZ-F1 orphan receptor loci. Three DHR3 binding sites were identified downstream from the start site of betaFTZ-F1 transcription, further indicating that this gene is a direct target of DHR3 regulation. Ectopic expression of DHR3 revealed that the polytene chromosome binding pattern is of functional significance. DHR3 is sufficient to repress BR-C, E74A, E75A and E78B transcription as well as induce betaFTZ-F1. DHR3 thus appears to function as a switch that defines the larval-prepupal transition by arresting the early regulatory response to ecdysone at puparium formation and facilitating the induction of the betaFTZ-F1 competence factor in mid-prepupae. This study also provides evidence for direct cross-regulation among orphan members of the nuclear receptor superfamily and further implicates these genes as critical transducers of the hormonal signal during the onset of Drosophila metamorphosis.
Coordination of larval and prepupal gene expression by the DHR3 orphan receptor during Drosophila metamorphosis
G.T. Lam, C. Jiang, C.S. Thummel; Coordination of larval and prepupal gene expression by the DHR3 orphan receptor during Drosophila metamorphosis. Development 1 May 1997; 124 (9): 1757–1769. doi: https://doi.org/10.1242/dev.124.9.1757
Download citation file:
Advertisement
Cited by
Development presents...
Our successful webinar series continues in 2021, with early-career researchers presenting their papers and a chance to virtually network with the developmental biology community afterwards. Here, Krisztina Ötvös tells us about the role link between nitrogen, auxin and root cell divisions.
Save your spot at our next session:
14 April
Time: 17:00 BST
Chaired by: François Guillemot
Join our mailing list to receive news and updates on the series.
The people behind the papers - Vincent Mouilleau, Célia Vaslin and Stéphane Nedelec
First authors, Vincent Mouilleau and Célia Vaslin, and their supervisor Stéphane Nedelec, talk about their latest work on HOX regulation, its potential clinical impact and where the story will take the Nedelec lab.
Special issue: call for papers
The Immune System in Development and Regeneration
Guest editors: Florent Ginhoux and Paul Martin
Submission deadline: 1 September 2021
Publication: Spring 2022
Upcoming grant deadlines
Grants awarded by The Company of Biologists help scientists travel, attend events and host sustainable activities. Make a note of the upcoming application deadlines and find out more about the grants on offer:
Sustainable Conferencing Grants
17 May 2021
Travelling Fellowships
31 May 2021
Scientific Meeting Grants
4 June 2021