title: The chicken HS4 insulator element does not protect the H19 ICR from differential DNA methylation in yeast artificial chromosome transgenic mouse.
abstract: Mono-allelic expression at the mouse IGF2/H19 locus is controlled by differential allelic DNA methylation of the imprinting control region (ICR). Because a randomly integrated H19 ICR fragment, when incorporated into the genome of transgenic mice (TgM), was allele-specifically methylated in somatic, but not in germ cells, it was suggested that allele-discriminating epigenetic signature, set within or somewhere outside of the Tg H19 ICR fragment in germ cells, was later translated into a differential DNA methylation pattern. To test if the chicken β-globin HS4 (cHS4) chromatin insulator might interfere with methylation imprinting establishment at the H19 ICR, we inserted the H19 ICR fragment, flanked by a set of floxed cHS4 core sequences, into a human β-globin locus YAC and generated TgM (insulated ICR' TgM). As controls, the cHS4 sequences were removed from one side (5'HS4-deleted ICR') or both sides (pseudo-WT ICR') of the insulated ICR' by in vivo cre-loxP recombination. The data show that while maternally inherited transgenic H19 ICR was not methylated in insulated ICR' TgM, it was significantly methylated upon paternal transmission, though the level was lower than in the pseudo-WT ICR' control. Because this reduced level of methylation was also observed in the 5'HS4-deleted ICR' TgM, we speculate that the phenotype is due to VEZF1-dependent demethylation activity, rather than the insulator function, borne in cHS4. Collectively, although we cannot rule out the possibility that cHS4 is incapable of blocking an allele-discriminating signal from outside of the transgene, the epigenetic signature appears to be marked intrinsically within the H19 ICR.
authors.affiliation: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors.forename: Eiichi
authors.initials: E
authors.lastname: Okamura
authors.forename: Hitomi
authors.initials: H
authors.lastname: Matsuzaki
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Fukamizu
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanimoto
mesh_terms: D000818:Animals; D002645:Chickens / Q000235:genetics*; D022201:Chromosomes, Artificial / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics*; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D038101:Insulator Elements / Q000235:genetics*; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D051379:Mice; D008822:Mice, Transgenic; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D007335:Insulin-Like Growth Factor II
references.citation: Trends Genet. 2008 Apr;24(4):195-204
references.pmid: 18329128
references.citation: Cell Res. 2011 Mar;21(3):466-73
references.pmid: 21283132
references.citation: Nature. 2007 Aug 9;448(7154):714-7
references.pmid: 17687327
references.citation: Hum Mol Genet. 2010 Apr 1;19(7):1190-8
references.pmid: 20047949
references.citation: Hum Mol Genet. 2009 Sep 15;18(18):3375-83
references.pmid: 19515852
references.citation: Mol Cell Biol. 2004 May;24(9):3588-95
references.pmid: 15082756
references.citation: PLoS One. 2010 Sep 08;5(9):e12630
references.pmid: 20838620
references.citation: Nat Genet. 2004 Aug;36(8):883-8
references.pmid: 15273688
references.citation: Hum Mol Genet. 2007 Oct 1;16(19):2272-80
references.pmid: 17616512
references.citation: Cell. 1999 Aug 6;98(3):387-96
references.pmid: 10458613
references.citation: Genome Res. 2009 Aug;19(8):1338-49
references.pmid: 19584098
references.citation: Nucleic Acids Res. 2010 Jul;38(13):4246-53
references.pmid: 20223770
references.citation: Mol Cell Biol. 2007 Nov;27(22):7991-8002
references.pmid: 17846119
references.citation: Mol Cell Biol. 2008 Jan;28(1):71-82
references.pmid: 17967893
references.citation: Reproduction. 2010 Sep;140(3):411-23
references.pmid: 20501788
references.citation: EMBO Rep. 2009 Nov;10(11):1235-41
references.pmid: 19834512
references.citation: Nature. 1993 Nov 25;366(6453):362-5
references.pmid: 8247133
references.citation: Cell Res. 2011 Aug;21(8):1172-81
references.pmid: 21606950
references.citation: Mol Cell Biol. 2010 Mar;30(5):1108-15
references.pmid: 20038532
references.citation: Cell. 1992 Jun 12;69(6):915-26
references.pmid: 1606615
references.citation: Genes Dev. 2009 Sep 15;23(18):2124-33
references.pmid: 19759261
references.citation: Nature. 2001 Nov 15;414(6861):277-83
references.pmid: 11713521
references.citation: Development. 2002 Feb;129(4):897-904
references.pmid: 11861473
references.citation: EMBO J. 2012 Feb 1;31(3):606-15
references.pmid: 22117218
references.citation: Nature. 2004 Jun 24;429(6994):900-3
references.pmid: 15215868
references.citation: Nature. 2012 Jun 03;486(7403):415-9
references.pmid: 22722204
references.citation: Proc Natl Acad Sci U S A. 2005 Jul 19;102(29):10250-5
references.pmid: 16006531
references.citation: Mol Cell Biol. 2009 Sep;29(17):4595-603
references.pmid: 19546235
references.citation: Curr Opin Genet Dev. 2012 Apr;22(2):72-8
references.pmid: 22195775
references.citation: Mol Cell. 2004 Nov 5;16(3):453-63
references.pmid: 15525517
references.citation: Hum Mol Genet. 2000 Nov 22;9(19):2885-94
references.pmid: 11092765
references.citation: Mol Cell Biol. 2003 Dec;23(24):8946-52
references.pmid: 14645507
references.citation: Nature. 2000 May 25;405(6785):482-5
references.pmid: 10839546
references.citation: Nature. 2009 Jul 23;460(7254):473-8
references.pmid: 19525931
references.citation: EMBO J. 2007 Feb 7;26(3):720-9
references.pmid: 17255950
references.citation: Mol Cell Biol. 1998 Jun;18(6):3350-6
references.pmid: 9584175
references.citation: Genes Dev. 2009 Jan 1;23(1):105-17
references.pmid: 19136628
references.citation: PLoS Genet. 2010 Jan;6(1):e1000804
references.pmid: 20062523
references.citation: Nature. 2000 May 25;405(6785):486-9
references.pmid: 10839547
references.citation: Nucleic Acids Res. 1999 Aug 1;27(15):3130-7
references.pmid: 10454609
references.citation: Proc Natl Acad Sci U S A. 1997 Jan 21;94(2):575-80
references.pmid: 9012826
references.citation: Proc Natl Acad Sci U S A. 2002 May 14;99(10):6883-8
references.pmid: 12011446