The dorsal morphogen is a sequence-specific DNA-binding protein that interacts with a long-range repression element in Drosophila.
A gradient of the maternal morphogen dorsal (dl) establishes dorsal-ventral (D-V) polarity in the early Drosophila embryo. The dl concentration gradient is initiated by regulated nuclear transport, and only protein that enters nuclei is active in the D-V patterning process. Here we show that dl is a DNA-binding protein that specifically interacts with distal sequences of the zerknüllt (zen) promoter, one of the genetic targets of the morphogen. These zen sequences have the properties of a silencer element and can act over long distances to repress the expression of a heterologous promoter. The dl protein recognizes a sequence motif similar to that of the mammalian transcriptional activator NF-kappa B, which was shown to contain extensive homology with dl and the oncoprotein rel. We present evidence that the DNA-binding activity of the dl protein is mediated by the region of homology (the rel domain) conserved in the rel and NF-kappa B proteins.
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Department of Biological Sciences, Fairchild Center, Columbia University, New York, New York 10027.
Kraut
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Levine
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Rushlow
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CA
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000502:physiology; D008969:Molecular Sequence Data; D009024:Morphogenesis; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D015345:Oligonucleotide Probes; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping
D004268:DNA-Binding Proteins; D016328:NF-kappa B; D015345:Oligonucleotide Probes