title: Spatial and temporal control elements of the Drosophila engrailed gene.
abstract: engrailed (en) is a segmentation gene expressed in a series of stripes throughout embryonic development. Here, I show that regulatory sequences for striped expression are present within the first intron of en. The 1-kb intron is able to confer striped expression early, but not late, in development. This shows that different regulatory sequences are required for en stripes at different times in development. Furthermore, stripes generated by the intron are coincident with en stripes in a wild-type background but behave differently from endogenous engrailed stripes in some segmentation mutant backgrounds. Thus, although the intron can induce apparently normal stripes, it lacks some of the regulatory sequences present within the endogenous gene. These experiments suggest that multiple regulatory programs control an expression in stripes, and each may be able to confer "normal" spatial regulation independently.
authors.affiliation: Laboratory of Cellular and Molecular Biology, Food and Drug Administration, Bethesda, Maryland 20892.
authors.forename: J A
authors.initials: JA
authors.lastname: Kassis
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D005796:Genes; D007438:Introns; D007763:Lac Operon; D009928:Organ Specificity; D010641:Phenotype; D012045:Regulatory Sequences, Nucleic Acid; D013045:Species Specificity