The Drosophila EcR gene encodes an ecdysone receptor, a new member of the steroid receptor superfamily.
The steroid hormone ecdysone triggers coordinate changes in Drosophila tissue development that result in metamorphosis. To advance our understanding of the genetic regulatory hierarchies controlling this tissue response, we have isolated and characterized a gene, EcR, for a new steroid receptor homolog and have shown that it encodes an ecdysone receptor. First, EcR protein binds active ecdysteroids and is antigenically indistinguishable from the ecdysone-binding protein previously observed in extracts of Drosophila cell lines and tissues. Second, EcR protein binds DNA with high specificity at ecdysone response elements. Third, ecdysone-responsive cultured cells express EcR, whereas ecdysone-resistant cells derived from them are deficient in EcR. Expression of EcR in such resistant cells by transfection restores their ability to respond to the hormone. As expected, EcR is nuclear and found in all ecdysone target tissues examined. Furthermore, the EcR gene is expressed at each developmental stage marked by a pulse of ecdysone.
Department of Biochemistry, Stanford University Medical Center, California 94305.
M R
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Koelle
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Talbot
W A
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Segraves
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Bender
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Cherbas
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Hogness
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D004440:Ecdysone / Q000378:metabolism; D005091:Exons; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D011987:Receptors, Steroid / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014162:Transfection
D011987:Receptors, Steroid; D011994:Recombinant Proteins; C055469:ecdysone receptor; D004440:Ecdysone; D004247:DNA