title: GAGA factor repression of transcription is a rare event but the negative regulation of Trl is conserved in Drosophila species.
abstract: GAGA is a highly conserved Drosophila transcription factor encoded by the Trithorax-like (Trl) gene. While GAGA usually activates transcription, it represses its own promoter. Here we show that GAGA-mediated repression of Trl is conserved between two distant Drosophila species. A detailed promoter study showed that GAGA repressive activity can't be attributed to any discrete element in the Trl promoter. Genome-wide analysis of the transcriptome in S2 cells indicated that repression of Trl is very likely unique, being GAGA factor a transactivator for all the other promoters. Taken together, our results suggest a new mechanism to explain GAGA-mediated repression that involves a dose-dependent change in the architecture of the Trl promoter.
authors.affiliation: Departament. de Genòmica Molecular, Institut de Biologia Molecular de Barcelona-CSIC, Parc Científic de Barcelona, 08028 Barcelona, Spain; Cell and Developmental Biology Programme, Institute for Research in Biomedicine, Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Piñeyro
authors.forename: Marta
authors.initials: M
authors.lastname: Blanch
authors.forename: Martí
authors.initials: M
authors.lastname: Badal
authors.forename: Ana
authors.initials: A
authors.lastname: Kosoy
authors.forename: Jordi
authors.initials: J
authors.lastname: Bernués
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics*; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C063460:Trl protein, Drosophila
keywords: Drosophila; GAGA factor; Mechanism of repression; Regulation of transcription