Role of CTCF Protein in Regulating FMR1 Locus Transcription

Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of...

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Published inPLoS genetics Vol. 9; no. 7; p. e1003601
Main Authors Lanni, Stella, Goracci, Martina, Borrelli, Loredana, Mancano, Giorgia, Chiurazzi, Pietro, Moscato, Umberto, Ferrè, Fabrizio, Helmer-Citterich, Manuela, Tabolacci, Elisabetta, Neri, Giovanni
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LanguageEnglish
Published United States Public Library of Science 01.07.2013
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Abstract Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.
AbstractList Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.
Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMWR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.
  Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.
Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript (FMR1-AS1), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.
Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation). An antisense transcript ( FMR1 - AS1 ), starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM) alleles present the same boundary described in wild type (WT) alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1 -mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis. Fragile X syndrome is the most common cause of inherited intellectual disability, accounting for about 1∶3000 males and 1∶4000 females. It is caused by a dynamic mutation of FMR1 , a gene mapping on the X chromosome and containing a CGG repeat in its promoter region. Expansion of this unstable sequence beyond 200 repeats (full mutation) is followed by DNA methylation and histone changes, leading to the transcriptional inactivation of FMR1 and to the lack of the FMRP protein. Recently, an antisense transcript ( FMR1-AS1 ) spanning the CGG repeats and a region of transition of DNA methylation (boundary) located upstream of the CGG repeats have been identified in transcriptional active FMR1 alleles. Several nuclear proteins bound to the methylation boundary have been described, such as the zinc-finger protein CTCF, the first known insulator in mammals. This protein is an important transcriptional regulator of genes harboring trinucleotide repeats and it is mostly active in chromatin organization. For the first time, we have investigated the role of CTCF protein in the transcriptional regulation of the FMR1 gene. Our results define a complex role for CTCF acting through chromatin organization of the FMR1 locus.
Audience Academic
Author Neri, Giovanni
Chiurazzi, Pietro
Moscato, Umberto
Mancano, Giorgia
Tabolacci, Elisabetta
Ferrè, Fabrizio
Borrelli, Loredana
Lanni, Stella
Goracci, Martina
Helmer-Citterich, Manuela
AuthorAffiliation The Hospital for Sick Children and University of Toronto, Canada
3 Dipartimento di Biologia, Università di Roma “Tor Vergata”, Rome, Italy
2 Istituto di Igiene, Università Cattolica del S. Cuore, Rome, Italy
1 Istituto di Genetica Medica, Università Cattolica del S. Cuore, Rome, Italy
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BackLink https://www.ncbi.nlm.nih.gov/pubmed/23874213$$D View this record in MEDLINE/PubMed
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Cites_doi 10.1093/nar/gkm875
10.1002/ajmg.a.34113
10.1074/jbc.M009629200
10.1038/sj.ejhg.5201393
10.1038/ejhg.2008.130
10.1016/0092-8674(91)90397-H
10.1016/j.molcel.2005.09.002
10.1073/pnas.0605343103
10.1038/msb.2010.79
10.1093/nar/gkr750
10.1042/BJ20111417
10.1016/S0092-8674(00)81967-4
10.1002/bies.200900118
10.1128/MCB.16.6.2802
10.1038/nsmb.1876
10.1016/j.neuron.2011.05.027
10.1038/nature06634
10.1038/35013100
10.1016/S0960-9822(00)00597-2
10.1101/gr.136101.111
10.1093/hmg/ddq427
10.1016/S0070-2153(07)80009-3
10.1038/35013106
10.1016/j.molcel.2009.04.001
10.1128/MCB.01993-06
10.1128/MCB.01326-07
10.1016/j.cell.2009.06.001
10.1016/S0168-9525(01)02366-6
10.1083/jcb.201101021
10.1016/S0092-8674(03)00079-5
10.1007/s00439-002-0723-5
10.1016/j.gde.2007.08.005
10.1016/0092-8674(91)90125-I
10.1016/j.ajhg.2009.09.018
10.1371/journal.pone.0012847
10.1128/MCB.13.12.7612
10.1093/hmg/ddi024
10.1038/ng.857
10.1038/nprot.2007.116
10.1016/j.stem.2007.09.001
10.1371/journal.pone.0007914
10.1093/hmg/7.1.109
10.1093/nar/gkf434
10.1093/hmg/ddm293
10.1158/0008-5472.CAN-05-2481
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2013 Lanni et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited: Lanni S, Goracci M, Borrelli L, Mancano G, Chiurazzi P, et al. (2013) Role of CTCF Protein in Regulating FMR1 Locus Transcription. PLoS Genet 9(7): e1003601. doi:10.1371/journal.pgen.1003601
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– notice: 2013 Lanni et al 2013 Lanni et al
– notice: 2013 Lanni et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited: Lanni S, Goracci M, Borrelli L, Mancano G, Chiurazzi P, et al. (2013) Role of CTCF Protein in Regulating FMR1 Locus Transcription. PLoS Genet 9(7): e1003601. doi:10.1371/journal.pgen.1003601
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Conceived and designed the experiments: SL MG LB ET FF. Performed the experiments: SL MG LB FF. Analyzed the data: UM FF. Contributed reagents/materials/analysis tools: ET FF MHC GN. Wrote the paper: SL MG ET PC GN FF. Contributes to the new experiments of the revised manuscript: GM.
The authors have declared that no competing interests exist.
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References M Pieretti (ref3) 1991; 66
JD Cleary (ref29) 2010; 17
F Pirozzi (ref1) 2011; 8
F Zalfa (ref5) 2003; 112
JA Wallace (ref19) 2007; 17
JE Phillips (ref14) 2009; 137
P Chiurazzi (ref10) 1998; 7
GN Filippova (ref18) 1996; 16
S Huang (ref42) 2007; 27
E Tabolacci (ref8) 2008; 16
R Pietrobono (ref11) 2002; 30
D Kumari (ref44) 2001; 276
DH Cho (ref28) 2005; 20
M Witcher (ref40) 2009; 34
BL Sopher (ref31) 2011; 70
E Tabolacci (ref4) 2005; 13
R Pietrobono (ref7) 2005; 14
AT Hark (ref26) 2000; 405
AC Bell (ref48) 1999; 98
PD Ladd (ref33) 2007; 16
J Dostie (ref35) 2007; 2
AJ Verkerk (ref2) 1991; 65
N Gheldof (ref47) 2006; 103
L Bao (ref34) 2008; 36
J Wang (ref43) 2012; 40
H Zhang (ref46) 2011; 193
VV Lobanenkov (ref17) 1990; 5
H Wang (ref27) 2012; 22
A Naumann (ref13) 2009; 85
L Handoko (ref22) 2011; 43
M Zampieri (ref38) 2012; 441
HJ Smeets (ref6) 1995; 11
R Ohlsson (ref16) 2001; 17
RJ Taft (ref45) 2011; 4
AC Bell (ref24) 2000; 405
C Kanduri (ref25) 2000; 10
KS Wendt (ref36) 2008; 451
M Botta (ref23) 2010; 6
I De Biase (ref32) 2009; 4
I Chernukhin (ref37) 2007; 27
A López Castel (ref30) 2011; 20
R Willemsen (ref9) 2002; 110
GN Filippova (ref20) 2008; 80
R Ohlsson (ref21) 2010; 32
EM Klenova (ref15) 1993; 13
KM McGarvey (ref41) 2006; 66
R Eiges (ref12) 2007; 1
JW Chang (ref39) 2010; 5
References_xml – volume: 36
  start-page: D83
  year: 2008
  ident: ref34
  article-title: CTCFBSDB: a CTCF-binding site database for characterization of vertebrate genomic insulators
  publication-title: Nucleic Acids Res
  doi: 10.1093/nar/gkm875
– volume: 8
  start-page: 1803
  year: 2011
  ident: ref1
  article-title: The FRAXopathies: Definition, overview, and update
  publication-title: Am J Med Genet part A
  doi: 10.1002/ajmg.a.34113
– volume: 276
  start-page: 4357
  year: 2001
  ident: ref44
  article-title: Interaction of the transcription factors USF1, USF2, and alpha -Pal/Nrf-1 with the FMR1 promoter. Implications for Fragile X mental retardation syndrome
  publication-title: J Biol Chem
  doi: 10.1074/jbc.M009629200
– volume: 13
  start-page: 641
  year: 2005
  ident: ref4
  article-title: Differential epigenetic modifications in the FMR1 gene of the fragile X syndrome after reactivating pharmacological treatments
  publication-title: Eur J Hum Genet
  doi: 10.1038/sj.ejhg.5201393
– volume: 16
  start-page: 1487
  year: 2008
  ident: ref8
  article-title: Epigenetic analysis reveals a euchromatic configuration in the FMR1 unmethylated full mutations
  publication-title: Eur J Hum Genet
  doi: 10.1038/ejhg.2008.130
– volume: 65
  start-page: 905
  year: 1991
  ident: ref2
  article-title: Identification of a gene (FMR-1) containing a CGG repeat coincident with a breakpoint cluster region exhibiting length variation in fragile X syndrome
  publication-title: Cell
  doi: 10.1016/0092-8674(91)90397-H
– volume: 20
  start-page: 483
  year: 2005
  ident: ref28
  article-title: Antisense transcription and heterochromatin at the DM1 CTG repeats are constrained by CTCF
  publication-title: Mol Cell
  doi: 10.1016/j.molcel.2005.09.002
– volume: 103
  start-page: 12463
  year: 2006
  ident: ref47
  article-title: The active FMR1 promoter is associated with a large domain of altered chromatin conformation with embedded local histone modifications
  publication-title: Proc Natl Acad Sci USA
  doi: 10.1073/pnas.0605343103
– volume: 6
  start-page: 426
  year: 2010
  ident: ref23
  article-title: Intra- and inter-chromosomal interactions correlate with CTCF binding genome wide
  publication-title: Mol Syst Biol
  doi: 10.1038/msb.2010.79
– volume: 40
  start-page: 511
  year: 2012
  ident: ref43
  article-title: Genome-wide prediction and analysis of human chromatin boundary elements
  publication-title: Nucleic Acids Res
  doi: 10.1093/nar/gkr750
– volume: 441
  start-page: 645
  year: 2012
  ident: ref38
  article-title: ADP-ribose polymers localized on Ctcf-Parp1-Dnmt1 complex prevent methylation of Ctcf target sites
  publication-title: Biochem J
  doi: 10.1042/BJ20111417
– volume: 98
  start-page: 387
  year: 1999
  ident: ref48
  article-title: The protein CTCF is required for the enhancer blocking activity of vertebrate insulators
  publication-title: Cell
  doi: 10.1016/S0092-8674(00)81967-4
– volume: 32
  start-page: 37
  year: 2010
  ident: ref21
  article-title: Does CTCF mediate between nuclear organization and gene expression?
  publication-title: Bioessays
  doi: 10.1002/bies.200900118
– volume: 16
  start-page: 2802
  year: 1996
  ident: ref18
  article-title: An exceptionally conserved transcriptional repressor, CTCF, employs different combinations of zinc fingers to bind diverged promoter sequences of avian and mammalian c-myc oncogenes
  publication-title: Mol Cell Biol
  doi: 10.1128/MCB.16.6.2802
– volume: 17
  start-page: 1079
  year: 2010
  ident: ref29
  article-title: Tissue- and age-specific DNA replication patterns at the CTG/CAG-expanded human myotonic dystrophy type 1 locus
  publication-title: Nat Struct Mol Biol
  doi: 10.1038/nsmb.1876
– volume: 70
  start-page: 1071
  year: 2011
  ident: ref31
  article-title: CTCF regulates ataxin-7 expression through promotion of a convergently transcribed, antisense noncoding RNA
  publication-title: Neuron
  doi: 10.1016/j.neuron.2011.05.027
– volume: 451
  start-page: 796
  year: 2008
  ident: ref36
  article-title: Cohesin mediates transcriptional insulation by CCCTC-binding factor
  publication-title: Nature
  doi: 10.1038/nature06634
– volume: 405
  start-page: 482
  year: 2000
  ident: ref24
  article-title: Methylation of a CTCF-dependent boundary controls imprinted expression of the Igf2 gene
  publication-title: Nature
  doi: 10.1038/35013100
– volume: 10
  start-page: 853
  year: 2000
  ident: ref25
  article-title: Functional association of CTCF with the insulator upstream of the H19 gene is parent of origin-specific and methylation-sensitive
  publication-title: Curr Biol
  doi: 10.1016/S0960-9822(00)00597-2
– volume: 22
  start-page: 1680
  year: 2012
  ident: ref27
  article-title: Widespread plasticity in CTCF occupancy linked to DNA methylation
  publication-title: Genome Res
  doi: 10.1101/gr.136101.111
– volume: 20
  start-page: 1
  year: 2011
  ident: ref30
  article-title: Expanded CTG repeat demarcates a boundary for abnormal CpG methylation in myotonic dystrophy patient tissues
  publication-title: Hum Mol Genet
  doi: 10.1093/hmg/ddq427
– volume: 5
  start-page: 1743
  year: 1990
  ident: ref17
  article-title: A novel sequence specific DNA binding protein which interacts with three regularly spaced direct repeats of the CCCTC-motif in the 5′-flanking sequence of the chicken c-myc gene
  publication-title: Oncogene
– volume: 80
  start-page: 337
  year: 2008
  ident: ref20
  article-title: Genetics and epigenetics of the multifunctional protein CTCF
  publication-title: Curr Top Dev Biol
  doi: 10.1016/S0070-2153(07)80009-3
– volume: 405
  start-page: 486
  year: 2000
  ident: ref26
  article-title: CTCF mediates methylation-sensitive enhancer-blocking activity at the H19/Igf2 locus
  publication-title: Nature
  doi: 10.1038/35013106
– volume: 34
  start-page: 271
  year: 2009
  ident: ref40
  article-title: Epigenetic silencing of the p16(INK4a) tumor suppressor is associated with loss of CTCF binding and a chromatin boundary
  publication-title: Mol Cell
  doi: 10.1016/j.molcel.2009.04.001
– volume: 27
  start-page: 1631
  year: 2007
  ident: ref37
  article-title: CTCF interacts with and recruits the largest subunit of RNA polymerase II to CTCF target sites genome-wide
  publication-title: Mol Cell Biol
  doi: 10.1128/MCB.01993-06
– volume: 27
  start-page: 7991
  year: 2007
  ident: ref42
  article-title: USF1 recruits histone modification complexes and is critical for maintenance of a chromatin barrier
  publication-title: Mol Cell Biol
  doi: 10.1128/MCB.01326-07
– volume: 137
  start-page: 1194
  year: 2009
  ident: ref14
  article-title: CTCF: master weaver of the genome
  publication-title: Cell
  doi: 10.1016/j.cell.2009.06.001
– volume: 17
  start-page: 520
  year: 2001
  ident: ref16
  article-title: CTCF is a uniquely versatile transcription regulator linked to epigenetics and disease
  publication-title: Trends Genet
  doi: 10.1016/S0168-9525(01)02366-6
– volume: 193
  start-page: 475
  year: 2011
  ident: ref46
  article-title: Interruption of intrachromosomal looping by CCCTC binding factor decoy proteins abrogates genomic imprinting of human insulin-like growth factor II
  publication-title: J Cell Biol
  doi: 10.1083/jcb.201101021
– volume: 112
  start-page: 317
  year: 2003
  ident: ref5
  article-title: The fragile X syndrome protein FMRP associates with BC1 RNA and regulates the translation of specific mRNAs at synapses
  publication-title: Cell
  doi: 10.1016/S0092-8674(03)00079-5
– volume: 110
  start-page: 601
  year: 2002
  ident: ref9
  article-title: Timing of the absence of FMR1 expression in full mutation chorionic villi
  publication-title: Hum Genet
  doi: 10.1007/s00439-002-0723-5
– volume: 17
  start-page: 400
  year: 2007
  ident: ref19
  article-title: We gather together: insulators and genome organization
  publication-title: Curr Opin Genet Dev
  doi: 10.1016/j.gde.2007.08.005
– volume: 66
  start-page: 817
  year: 1991
  ident: ref3
  article-title: Absence of expression of the FMR-1 gene in fragile X syndrome
  publication-title: Cell
  doi: 10.1016/0092-8674(91)90125-I
– volume: 85
  start-page: 606
  year: 2009
  ident: ref13
  article-title: A distinct DNA-methylation boundary in the 5′-upstream sequence of the FMR1 promoter binds nuclear proteins and is lost in fragile X syndrome
  publication-title: Am J Hum Genet
  doi: 10.1016/j.ajhg.2009.09.018
– volume: 5
  start-page: e12847
  year: 2010
  ident: ref39
  article-title: Distinct epigenetic domains separated by a CTCF bound insulator between the tandem genes, BLU and RASSF1A
  publication-title: PLoS One
  doi: 10.1371/journal.pone.0012847
– volume: 4
  start-page: 1
  year: 2011
  ident: ref45
  article-title: The relationship between transcription initiation RNAs and CCCTC-binding factor (CTCF) localization
  publication-title: Epigenetics Chromatin
– volume: 13
  start-page: 7612
  year: 1993
  ident: ref15
  article-title: CTCF, a conserved nuclear factor required for optimal transcriptional activity of the chicken c-myc gene, is an 11-Zn-finger protein differentially expressed in multiple forms
  publication-title: Mol Cell Biol
  doi: 10.1128/MCB.13.12.7612
– volume: 14
  start-page: 267
  year: 2005
  ident: ref7
  article-title: Molecular dissection of the events leading to inactivation of the FMR1 gene
  publication-title: Hum Mol Genet
  doi: 10.1093/hmg/ddi024
– volume: 43
  start-page: 630
  year: 2011
  ident: ref22
  article-title: CTCF-mediated functional chromatin interactome in pluripotent cells
  publication-title: Nat Genet
  doi: 10.1038/ng.857
– volume: 2
  start-page: 988
  year: 2007
  ident: ref35
  article-title: Mapping networks of physical interactions between genomic elements using 5C technology
  publication-title: Nat Protoc
  doi: 10.1038/nprot.2007.116
– volume: 1
  start-page: 568
  year: 2007
  ident: ref12
  article-title: Developmental study of fragile X syndrome using human embryonic stem cells derived from preimplantation genetically diagnosed embryos
  publication-title: Cell Stem Cell
  doi: 10.1016/j.stem.2007.09.001
– volume: 11
  start-page: 331
  year: 1995
  ident: ref6
  article-title: Normal phenotype in two brothers with a full FMR1 mutation
  publication-title: Hum Mol Genet
– volume: 4
  start-page: e7914
  year: 2009
  ident: ref32
  article-title: Epigenetic silencing in Friedreich ataxia is associated with depletion of CTCF (CCCTC-binding factor) and antisense transcription
  publication-title: PLoS One
  doi: 10.1371/journal.pone.0007914
– volume: 7
  start-page: 109
  year: 1998
  ident: ref10
  article-title: In vitro reactivation of the FMR1 gene involved in fragile X syndrome
  publication-title: Hum Mol Genet
  doi: 10.1093/hmg/7.1.109
– volume: 30
  start-page: 3278
  year: 2002
  ident: ref11
  article-title: Quantitative analysis of DNA demethylation and transcriptional reactivation of the FMR1 gene in fragile X cells treated with 5-azadeoxycytidine
  publication-title: Nucleic Acids Res
  doi: 10.1093/nar/gkf434
– volume: 16
  start-page: 3174
  year: 2007
  ident: ref33
  article-title: An antisense transcript spanning the CGG repeat region of FMR1 is upregulated in premutation carriers but silenced in full mutation individuals
  publication-title: Hum Mol Genet
  doi: 10.1093/hmg/ddm293
– volume: 66
  start-page: 3541
  year: 2006
  ident: ref41
  article-title: Silenced tumor suppressor genes reactivated by DNA demethylation do not return to a fully euchromatic chromatin state
  publication-title: Cancer Res
  doi: 10.1158/0008-5472.CAN-05-2481
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Snippet Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and...
Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and...
  Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and...
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StartPage e1003601
SubjectTerms Binding Sites
Biology
CCCTC-Binding Factor
Cell Line, Tumor
CpG Islands - genetics
Deoxyribonucleic acid
DNA
DNA Methylation
DNA sequencing
DNA-Binding Proteins
Drosophila Proteins - genetics
Drosophila Proteins - metabolism
Epigenesis, Genetic
Epigenetics
Exons - genetics
Experiments
Fragile X Mental Retardation Protein - genetics
Fragile X Mental Retardation Protein - metabolism
Fragile X syndrome
Fragile X Syndrome - genetics
Gene Expression Regulation
Genes
Genetic aspects
Genetic transcription
Humans
Introns - genetics
Methylation
Mutation
Nucleotide sequencing
Physiological aspects
Promoter Regions, Genetic
Proteins
Regulatory Sequences, Nucleic Acid
Repressor Proteins - genetics
Repressor Proteins - metabolism
Transcription, Genetic
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Title Role of CTCF Protein in Regulating FMR1 Locus Transcription
URI https://www.ncbi.nlm.nih.gov/pubmed/23874213
https://www.proquest.com/docview/1411633887
https://pubmed.ncbi.nlm.nih.gov/PMC3715420
https://doaj.org/article/58b9bd3447b847228d228093a7ec2ba5
http://dx.doi.org/10.1371/journal.pgen.1003601
Volume 9
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