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.
Inhibition of histone deacetylases alters allelic chromatin conformation at the imprinted U2af1-rs1 locus in mouse embryonic stem cells
Gregory, R. I.; O'Neill, L. P.; Randall, T. E.; Fournier, C.; Khosla, S.; Turner, B. M.; Feil, R.
J Biol Chem
2002-04-05 / vol 277 / pages 11728-34
10.1074/jbc.M105775200 M105775200 [pii]
0021-9258 (Print) 0021-9258 (Linking)
IGMM team(s) involved in this publication
Genomic Imprinting and Development
Female; Animals; Mice; DNA Methylation; Histones/metabolism; Male; Molecular Sequence Data; Alleles; Chromatin/*chemistry/metabolism; *Genomic Imprinting; Blotting, Southern; Polymerase Chain Reaction; Polymorphism, Single-Stranded Conformational; Reverse Transcriptase Polymerase Chain Reaction; Cell Differentiation; Mice, Inbred C57BL; *Histone Deacetylase Inhibitors; *Nerve Tissue Proteins; *Nuclear Proteins; *Ribonucleoproteins; Acetylation; Blotting, Northern; Cell Nucleus/metabolism; Deoxyribonuclease I/metabolism; Deoxyribonucleases/metabolism; Embryo, Mammalian/*cytology; Enzyme Inhibitors/*pharmacology; Fibroblasts/metabolism; Hydroxamic Acids/pharmacology; Kidney/metabolism; Lysine/chemistry; Precipitin Tests; Protein Conformation; Proteins/*genetics; Stem Cells/*metabolism; Time Factors; Tissue Distribution