A sequence conserved in vertebrate Hox gene introns functions as an enhancer regulated by posterior homeotic genes in Drosophila imaginal discs.
The intron of the mouse Hoxa-4 gene acts as a strong homeotic response element in Drosophila melanogaster leg imaginal discs. This activity depends on homeodomain binding sites present within a 30 bp conserved element, HB1, in the intron. A similar arrangement of homeodomain binding sites is found in many other potential homeotic target genes. HB1 activity in Drosophila imaginal discs is activated by Antennapedia and more posterior homeotic genes, but is not activated by more anterior genes. Testing a reporter gene construct with mutated binding sites in mouse embryos shows that HB1 is also active in the expression domains of posterior Hox genes in the mouse neural tube.
Keegan
L P
LP
Department of Cell Biology, Basel University Biozentrum, Switzerland.
Haerry
T E
TE
Crotty
D A
DA
Packer
A I
AI
Wolgemuth
D J
DJ
Gehring
W J
WJ
D000818:Animals; D051943:Antennapedia Homeodomain Protein; D001483:Base Sequence; D017124:Conserved Sequence / Q000502:physiology; D004268:DNA-Binding Proteins; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D004742:Enhancer Elements, Genetic / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D018398:Homeodomain Proteins / Q000502:physiology*; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000502:physiology; D007438:Introns / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D009687:Nuclear Proteins; D014157:Transcription Factors / Q000502:physiology
D051943:Antennapedia Homeodomain Protein; C497974:Antp protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C484111:Hoxa4 protein, mouse; D019476:Insect Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors