Intron of the mouse Hoxa-7 gene contains conserved homeodomain binding sites that can function as an enhancer element in Drosophila.
The 5' flanking sequences and the intron of the mouse Hoxa-7 gene were searched for regulatory elements that can function in Drosophila. Only the intron is able to activate a lacZ fusion gene in various tissues of Drosophila embryos. This enhancer function requires a cluster of three homeodomain binding sites (HB1-element) that are also found in the introns of other Hox genes as well as in a putative autoregulatory element of Ultrabithorax (Ubx), the Drosophila homolog of Hoxa-7. If a single binding site in the autoregulatory element of fushi tarazu (ftz) is replaced by the HB1-element of Hoxa-7, the expression pattern is altered and newly controlled by the homeotic gene caudal (cad). These data suggest that HB1 is a potential target for different homeodomain proteins of both vertebrates and invertebrates.
Haerry
T E
TE
Biozentrum, University of Basel, Switzerland.
Gehring
W J
WJ
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000502:physiology*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics / Q000502:physiology; D004625:Embryo, Nonmammalian / Q000502:physiology; D004742:Enhancer Elements, Genetic; D051717:Fushi Tarazu Transcription Factors; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D007438:Introns; D051379:Mice / Q000235:genetics*; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D051717:Fushi Tarazu Transcription Factors; D018398:Homeodomain Proteins; D014157:Transcription Factors; C066177:Ubx protein, Drosophila; C497169:ftz protein, Drosophila