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Identification and characterization of a Drosophila nuclear receptor with the ability to inhibit the ecdysone response.

ABSTRACT: In a search for retinoid X receptor-like molecules in Drosophila, we have identified an additional member of the nuclear receptor superfamily, XR78E/F. In the DNA-binding domain, XR78E/F is closely related to the mammalian receptor TR2, as well as to the nuclear receptors Coup-TF and Seven-up. We demonstrate that XR78E/F binds as a homodimer to direct repeats of the sequence AGGTCA. In transient transfection assays, XR78E/F represses ecdysone signaling in a DNA-binding-dependent fashion. XR78E/F has its highest expression in third-instar larvae and prepupae. These experiments suggest that XR78E/F may play a regulatory role in the transcriptional cascade triggered by the hormone ecdysone in Drosophila.

SUBMITTER: Zelhof AC

PROVIDER: S-EPMC40634 | biostudies-other | 1995 Nov

REPOSITORIES: biostudies-other

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Identification and characterization of a Drosophila nuclear receptor with the ability to inhibit the ecdysone response.

Zelhof A C AC Yao T P TP Evans R M RM McKeown M M

Proceedings of the National Academy of Sciences of the United States of America 19951101 23

In a search for retinoid X receptor-like molecules in Drosophila, we have identified an additional member of the nuclear receptor superfamily, XR78E/F. In the DNA-binding domain, XR78E/F is closely related to the mammalian receptor TR2, as well as to the nuclear receptors Coup-TF and Seven-up. We demonstrate that XR78E/F binds as a homodimer to direct repeats of the sequence AGGTCA. In transient transfection assays, XR78E/F represses ecdysone signaling in a DNA-binding-dependent fashion. XR78E/F ...[more]

PMID: 7479823

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Direct and widespread role for the nuclear receptor EcR in mediating the response to ecdysone in Drosophila

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