title: Insulator and silencer sequences in the imprinted region of human chromosome 11p15.5.
abstract: The imprinting of the genes on human chromosome 11p15.5 is thought to be controlled by two imprinting control regions located in two differentially methylated CpG islands upstream of the H19 gene (H19 DMR) and in intron 10 of the KCNQ1 gene (KvDMR). We have examined sequences in the human 11p15.5 genomic imprinted region for the presence of insulators and silencers using a position- and enhancer-dependent stable transfection assay. We have confirmed the existence of insulators in H19 DMR and discovered two novel insulators in the IGF2 gene. We have also found two novel silencer sequences; one is located in KvDMR, a region that is thought to contain the promoter for the KCNQ1OT1 transcript, and another is in the CDKN1C gene. We have demonstrated binding of CTCF protein in vitro to all the insulator and silencer sequences that we have detected. We discuss the differences in the regulation of imprinting controlled by the two imprinting control regions in chromosome 11p.
authors.affiliation: Department of Molecular and Medical Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8.
authors.forename: Minjie
authors.initials: M
authors.lastname: Du
authors.forename: Linda G
authors.initials: LG
authors.lastname: Beatty
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhou
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Lew
authors.forename: Christopher
authors.initials: C
authors.lastname: Schoenherr
authors.forename: Rosanna
authors.initials: R
authors.lastname: Weksberg
authors.forename: Paul D
authors.initials: PD
authors.lastname: Sadowski
mesh_terms: D000076246:CCCTC-Binding Factor; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D050761:Cyclin-Dependent Kinase Inhibitor p57; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D038101:Insulator Elements / Q000235:genetics*; D020014:K562 Cells; D051656:KCNQ Potassium Channels; D051657:KCNQ1 Potassium Channel; D008957:Models, Genetic; D009687:Nuclear Proteins / Q000235:genetics; D010957:Plasmids; D015221:Potassium Channels / Q000235:genetics; D024642:Potassium Channels, Voltage-Gated; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000235:genetics; D012097:Repressor Proteins / Q000378:metabolism; D037941:Silencer Elements, Transcriptional / Q000235:genetics*
chemical_list: D000076246:CCCTC-Binding Factor; C493964:CDKN1C protein, human; C000619697:CTCF protein, human; D050761:Cyclin-Dependent Kinase Inhibitor p57; D017931:DNA Primers; D004268:DNA-Binding Proteins; C094335:H19 long non-coding RNA; D051656:KCNQ Potassium Channels; D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human; D009687:Nuclear Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D012097:Repressor Proteins