title: Chromatin insulators.
abstract: Active and silenced chromatin domains are often in close juxtaposition to one another, and enhancer and silencer elements operate over large distances to regulate the genes in these domains. The lack of promiscuity in the function of these elements suggests that active mechanisms exist to restrict their activity. Insulators are DNA elements that restrict the effects of long-range regulatory elements. Studies on different insulators from different organisms have identified common themes in their mode of action. Numerous insulators map to promoters of genes or have binding sites for transcription factors and like active chromatin hubs and silenced loci, insulators also cluster in the nucleus. These results bring into focus potential conserved mechanisms by which these elements might function in the nucleus.
authors.affiliation: Unit on Chromatin and Transcription, NICHD/NIH, Bethesda, Maryland 20892, USA.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Valenzuela
authors.forename: Rohinton T
authors.initials: RT
authors.lastname: Kamakaka
mesh_terms: D000818:Animals; D000076246:CCCTC-Binding Factor; D002843:Chromatin / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D005914:Globins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D038101:Insulator Elements; D008954:Models, Biological; D063146:Polycomb-Group Proteins; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D037941:Silencer Elements, Transcriptional
chemical_list: D000076246:CCCTC-Binding Factor; C000619697:CTCF protein, human; D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins; D005914:Globins