title: Temporal regulation in development: negative and positive cis regulators dictate the precise timing of expression of a Drosophila chorion gene.
abstract: We have used germ-line transformation to dissect the cis regulatory elements responsible for the transcriptional control of an internally marked Drosophila chorion gene (s15-P) during development. A 73-base-pair segment of the proximal 5'-flanking DNA contains sequences essential for the tissue-specific expression and the precise "late" temporal regulation of that gene. A substitute s36-1 segment of similar location can provide the tissue-specific function and imparts an early temporal regulation characteristic of gene s36-1. Within the regulatory DNA of s15-P, at least three adjacent elements are recognizable: an essential operationally positive element (TCACGT) that is shared by s36-1 and other chorion genes, irrespective of temporal specificity; a second positive element that is required for the normal late expression of s15-P; and, farthest upstream, a negative element that represses precocious expression during the early choriogenic stages.
authors: Department of Cellular and Developmental Biology, Harvard University, Cambridge, MA 02138.
authors: B D
authors: BD
authors: Mariani
authors: J R
authors: JR
authors: Lingappa
authors: F C
authors: FC
authors: Kafatos
mesh_terms: D000818:Animals; D002823:Chorion / Q000166:cytology*; D002872:Chromosome Deletion; D004330:Drosophila; D005786:Gene Expression Regulation; D009154:Mutation; D013997:Time Factors