Functional analysis of an eye specific enhancer of the eyeless gene in Drosophila.
The development of the Drosophila compound eye requires the function of a set of evolutionarily conserved genes. Among these, the Drosophila Pax-6 gene eyeless (ey) plays a major role. ey has been considered a master control gene of eye development in the animal kingdom because targeted expression of ey and vertebrate as well as invertebrate homologs lead to the formation of ectopic eyes in Drosophila. We demonstrate that an intron of the ey gene contains an enhancer that regulates the eye specific expression of the gene in the eye disc primordia of embryos and in the eye imaginal discs of third instar larvae. Moreover, a 212-bp enhancer element is necessary and sufficient for the enhancer function. It is partially conserved in Drosophila hydei and contains putative Pax-6 Paired domain binding sites. We show that several binding sites are required for the eye specific expression, and, therefore, we propose a Pax-6-like molecule to be a positive transactivator for the eye specific ey expression. This transactivator recently has been identified as twin of eyeless, the second Pax-6 gene in Drosophila.
Hauck
B
B
Institut für Allgemeine Genetik (240), Universität Hohenheim, Garbenstrasse 30, D-70593 Stuttgart, Germany.
Gehring
W J
WJ
Walldorf
U
U
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D004330:Drosophila / Q000196:embryology* / Q000254:growth & development; D029721:Drosophila Proteins; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D005123:Eye / Q000254:growth & development*; D005136:Eye Proteins; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D018398:Homeodomain Proteins; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000235:genetics; D007438:Introns / Q000235:genetics; D007814:Larva / Q000254:growth & development; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D012097:Repressor Proteins; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D015533:Transcriptional Activation / Q000235:genetics
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D019476:Insect Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D012097:Repressor Proteins; C113278:ey protein, Drosophila