title: Characterization of new regulatory elements within the Drosophila bithorax complex.
abstract: The homeotic Abdominal-B (Abd-B) gene expression depends on a modular cis-regulatory region divided into discrete functional domains (iab) that control the expression of the gene in a particular segment of the fly. These domains contain regulatory elements implicated in both initiation and maintenance of homeotic gene expression and elements that separate the different domains. In this paper we have performed an extensive analysis of the iab-6 regulatory region, which regulates Abd-B expression at abdominal segment A6 (PS11), and we have characterized two new polycomb response elements (PREs) within this domain. We report that PREs at Abd-B cis-regulatory domains present a particular chromatin structure which is nuclease accessible all along Drosophila development and both in active and repressed states. We also show that one of these regions contains a dCTCF and CP190 dependent activity in transgenic enhancer-blocking assays, suggesting that it corresponds to the Fab-6 boundary element of the Drosophila bithorax complex.
authors.affiliation: Institut de Biologia Molecular de Barcelona, CSIC, Institut de Recerca Biomedica de Barcelona, IRBB, Parc Científic de Barcelona, Barcelona, Spain.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Pérez-Lluch
authors.forename: Sergi
authors.initials: S
authors.lastname: Cuartero
authors.forename: Fernando
authors.initials: F
authors.lastname: Azorín
authors.forename: M Lluïsa
authors.initials: ML
authors.lastname: Espinàs
mesh_terms: D000818:Animals; D003850:Deoxyribonuclease I / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D049750:Genome, Insect; D018398:Homeodomain Proteins / Q000235:genetics*; D063150:Polycomb Repressive Complex 1; D020218:Response Elements
chemical_list: C062393:Abd-B proteins, Drosophila; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C066770:Pc protein, Drosophila; D063150:Polycomb Repressive Complex 1; D003850:Deoxyribonuclease I