title: Inhibition of histone deacetylases alters allelic chromatin conformation at the imprinted U2af1-rs1 locus in mouse embryonic stem cells.
abstract: Most loci that are regulated by genomic imprinting have differentially methylated regions (DMRs). Previously, we showed that the DMRs of the mouse Snrpn and U2af1-rs1 genes have paternal allele-specific patterns of acetylation on histones H3 and H4. To investigate the maintenance of acetylation at these DMRs, we performed chromatin immunoprecipitation on trichostatin-A (TSA)-treated and control cells. In embryonic stem (ES) cells and fibroblasts, brief (6-h) TSA treatment induces global hyperacetylation of H3 and H4. In ES cells only, TSA led to a selective increase in maternal acetylation at U2af1-rs1, at lysine 5 of H4 and at lysine 14 of H3. TSA treatment of ES cells did not affect DNA methylation or expression of U2af1-rs1, but was sufficient to increase DNase I sensitivity along the maternal allele to a level comparable with that of the paternal allele. In fibroblasts, TSA did not alter U2af1-rs1 acetylation, and the parental alleles retained their differential DNase I sensitivity. At Snrpn, no changes in acetylation were observed in the TSA-treated cells. Our data suggest that the mechanisms regulating histone acetylation at DMRs are locus and developmental stage-specific and are distinct from those effecting global levels of acetylation. Furthermore, it seems that the allelic U2af1-rs1 acetylation determines DNase I sensitivity/chromatin conformation.
authors.affiliation: Institute of Molecular Genetics, CNRS UMR-5535, IFR-24, 34293 Montpellier cedex 5, France.
authors.forename: Richard I
authors.initials: RI
authors.lastname: Gregory
authors.forename: Laura P
authors.initials: LP
authors.lastname: O'Neill
authors.forename: Tamzin E
authors.initials: TE
authors.lastname: Randall
authors.forename: Cecile
authors.initials: C
authors.lastname: Fournier
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Khosla
authors.forename: Bryan M
authors.initials: BM
authors.lastname: Turner
authors.forename: Robert
authors.initials: R
authors.lastname: Feil
mesh_terms: D000107:Acetylation; D000483:Alleles; D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000737:chemistry* / Q000378:metabolism; D019175:DNA Methylation; D003850:Deoxyribonuclease I / Q000378:metabolism; D003851:Deoxyribonucleases / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D018392:Genomic Imprinting; D056572:Histone Deacetylase Inhibitors; D006657:Histones / Q000378:metabolism; D006877:Hydroxamic Acids / Q000494:pharmacology; D007668:Kidney / Q000378:metabolism; D008239:Lysine / Q000737:chemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011233:Precipitin Tests; D011487:Protein Conformation; D011506:Proteins / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; D013234:Stem Cells / Q000378:metabolism*; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D002843:Chromatin; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D006877:Hydroxamic Acids; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D011506:Proteins; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; C000607495:Zrsr1 protein, mouse; C012589:trichostatin A; D003851:Deoxyribonucleases; D003850:Deoxyribonuclease I; D008239:Lysine