title: Silencer and enhancer elements located at the 3'-side of the chicken and duck alpha-globin-encoding gene domains.
abstract: Enhancer activities have been observed in DNA fragments up to 1.36 kb long located on the 3'-side of the cluster of the three alpha-type globin-encoding genes in duck [Kretsovali et al., C.R. Acad. Sci. Paris 307 (1988) 563-568] and chicken [Knezetic and Felsenfeld, Mol. Cell. Biol. 9 (1989) 893-901]. We report here the identification of a chicken silencer element placed upstream from the three GATA-1 sites which constitute the core enhancer element in both species. This silencer element can autonomously reduce the activity of promoters for thymidine kinase and alpha D globin. Band shifts and DNase I footprinting experiments using nuclear extracts from thermosensitive avian erythroblastosis virus-transformed chicken erythroblasts led to the delineation of three sites for DNA-binding proteins within the silencer element.
authors.affiliation: Institut Jacques Monod, Paris, France.
authors.forename: F R
authors.initials: FR
authors.lastname: Targa
authors.forename: C V
authors.initials: CV
authors.lastname: de Moura Gallo
authors.forename: M
authors.initials: M
authors.lastname: Huesca
authors.forename: K
authors.initials: K
authors.lastname: Scherrer
authors.forename: L
authors.initials: L
authors.lastname: Marcaud
mesh_terms: D000818:Animals; D001483:Base Sequence; D002461:Cell Line, Transformed; D002645:Chickens / Q000235:genetics; D015500:Chloramphenicol O-Acetyltransferase / Q000378:metabolism; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000032:analysis; D003850:Deoxyribonuclease I / Q000378:metabolism; D015536:Down-Regulation; D004372:Ducks / Q000235:genetics; D004742:Enhancer Elements, Genetic; D004900:Erythroblasts; D005914:Globins / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D012150:Polymorphism, Restriction Fragment Length; D011200:Poultry / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000502:physiology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA / Q000379:methods; D012689:Sequence Homology, Nucleic Acid; D013937:Thymidine Kinase / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; D005914:Globins; D015500:Chloramphenicol O-Acetyltransferase; D013937:Thymidine Kinase; D003850:Deoxyribonuclease I