Core histone hyperacetylation co-maps with generalized DNase I sensitivity in the chicken beta-globin chromosomal domain.

Abstract

The distribution of core histone acetylation across the chicken beta‐globin locus has been mapped in 15 day chicken embryo erythrocytes by immunoprecipitation of mononucleosomes with an antibody recognizing acetylated histones, followed by hybridization probing at several points in the locus. A continuum of acetylation was observed, covering both genes and intergenic regions. Using the same probes, the generalized sensitivity to DNase I was mapped by monitoring the disappearance of intact genomic restriction fragments from Southern transfers. Close correspondence between the 33 kb of sensitive chromatin and the extent of acetylation indicates that one role of the modification could be the generation and/or maintenance of the open conformation. The precision of acetylation mapping makes it a possible approach to the definition of chromosomal domain boundaries.

DNA methylation and histone acetylation of rat methionine adenosyltransferase 1A and 2A genes is tissue-specific

“…Hence, MAT1A and MAT2A display a pattern of tissuespeci®c histone acetylation which closely correlates with their expression pro®les. This is consistent with previous observations showing that transcriptionally active chromatin is associated with enhanced histone acetylation levels [12,31].…”

“…Lower panels show the expression of either MAT1A (A) or MAT2A (B) in the di erent rat tissues as analyzed by Northern blotting. both MAT genes it is known that the pattern of DNA methylation can in¯uence the chromatin structure formed around a gene [10,11,28] and that the inactive chromatin structure associated with DNA methylation is important for the loss of transcriptional activity [12].…”

“…Gene-speci®c methylation patterns have been inversely correlated with gene activity. In this regard, DNA methylation may interfere with the binding of transcription factors and has been associated with the induction of a repressed state of the chromatin [10,12]. In addition to DNA methylation, core histone acetylation, a reversible post-translational modi®cation, has been associated with the transcriptional competence of the gene [13,14].…”

Chromatin remodeling and transcriptional activation: the cast (in order of appearance)

“…While its elementary particle, the nucleosome (Kornberg and Thomas, 1974), is ubiquitous (Noll, 1974), chromatin over a given DNA locus can assume a great variety of markedly distinct structural states in vivo (Hebbes et al, 1994(Hebbes et al, , 1988Tumbar et al, 1999;Wu, 1980;Zaret and Yamamoto, 1984): after all, many di erent buildings can be created using the same bricks. There is very strong correlative evidence connecting chromatin structure of a speci®c locus and the level of its transcriptional activity (for example, in addition to the studies just cited, Bone et al, 1994;Braunstein et al, 1993;Jeppesen and Turner, 1993;Kuo et al, 1998).…”

Evidence of epigenetic changes affecting the chromatin state of the retinoic acid receptor β2 promoter in breast cancer cells

“…On the contrary, in the MDA-MB-231 cells we saw that RA-induced RARb transcription is possible after treatment with TSA, a HDAC inhibitor, already known to induce chromatin alterations at RARb2 promoter in P19 cells . Analysis of the DNaseI sensitivity pattern, in and around RARb2, as well as the assessment of RARb2 histone acetylation state (Keshet et al, 1986;Hebbes et al, 1994;Eden et al, 1998), in both MCF7 and MDA-MB-231 cells will give us an idea of the relation between chromatin environments and RARb transcription. Moreover, these studies are expected to shed light on the relation of histone acetylation and methylation of the RARb2 promoter.…”