Competition for overlapping sites in the regulatory region of the Drosophila gene Krüppel.
A 730-base pair element regulates expression of the Drosophila gap gene Krüppel (Kr) in response to the fly anterior morphogen bicoid (bcd). Two hormone receptor-like proteins, encoded by the genes knirps (kni) and tailless (tll), bind specifically to the element. In vitro, kni protein competes with the homeodomain-containing bcd protein in binding to a 16-base pair target sequence. In vivo experiments suggest that both kni and tll act as competitive repressors of bcd-mediated activation of Kr. These results suggest a mechanism by which developmental genes can be regulated in response to an activating morphogen gradient antagonized by repressors.
Max-Planck-Institut für Biophysikalische Chemie, Abteilung Molekulare Entwicklungsbiologie, Göttingen, Federal Republic of Germany.
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Hoch
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Gerwin
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Taubert
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Jäckle
D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000235:genetics*; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D005786:Gene Expression Regulation; D005801:Genes, Homeobox; D005809:Genes, Regulator; D008969:Molecular Sequence Data; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D015183:Restriction Mapping; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D012097:Repressor Proteins; C074090:TLL protein, Drosophila; C074089:kni protein, Drosophila; D015500:Chloramphenicol O-Acetyltransferase; D001616:beta-Galactosidase