title: White as a reporter gene to detect transcriptional silencers specifying position-specific gene expression during Drosophila melanogaster eye development.
abstract: The white+ gene was used as a reporter to detect transcriptional silencer activity in the Drosophila genome. Changes in the spatial expression pattern of white were scored in the adult eye as nonuniform patterns of pigmentation. Thirty-six independent P[lacW] transposant lines were collected. These represent 12 distinct pigmentation patterns and probably 21 loci. The spatial pigmentation pattern is due to cis-acting suppression of white+ expression, and the suppression probably depends on cell position rather than cell type. The mechanism of suppression differs from inactivation by heterochromatin. In addition, activation of lacZ in P[lacW] occurs also in specific patterns in imaginal discs and embryos in many of the lines. The expression patterns of white+ and lacZ may reflect the activity of regulatory elements belonging to an endogenous gene near each P[lacW] insertion site. We speculate that these putative POSE (position-specific expression) genes may have a role in pattern formation of the eye as well as other imaginal structures. Three of the loci identified are optomotor-blind, engrailed and invected. teashirt is also implicated as a candidate gene. We propose that this "silencer trap"' may be an efficient way of identifying genes involved in imaginal pattern formation.
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Nankang Taipei, Republic of China.
authors.forename: Y H
authors.initials: YH
authors.lastname: Sun
authors.forename: C J
authors.initials: CJ
authors.lastname: Tsai
authors.forename: M M
authors.initials: MM
authors.lastname: Green
authors.forename: J L
authors.initials: JL
authors.lastname: Chao
authors.forename: C T
authors.initials: CT
authors.lastname: Yu
authors.forename: T J
authors.initials: TJ
authors.lastname: Jaw
authors.forename: J Y
authors.initials: JY
authors.lastname: Yeh
authors.forename: V N
authors.initials: VN
authors.lastname: Bolshakov
mesh_terms: D018528:ATP-Binding Cassette Transporters; D000818:Animals; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development; D005123:Eye / Q000254:growth & development*; D005127:Eye Color / Q000235:genetics; D005136:Eye Proteins; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D007301:Insect Hormones / Q000096:biosynthesis / Q000235:genetics*; D012045:Regulatory Sequences, Nucleic Acid; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D018528:ATP-Binding Cassette Transporters; D029721:Drosophila Proteins; D005136:Eye Proteins; D007301:Insect Hormones; C059254:w protein, Drosophila