Histones hyperacetylated

Stedman W, Deng Z, Lu F, Lieberman PM (2004) ORC, MCM, and histone hyperacetylation at the Kaposi s sarcoma-associated herpesvirus latent replication origin. J Virol 78 12566-12575 Steiner H, Haass C (2001) Nuclear signaling a common function of presenilin substrates J Mol Neurosci 17 193-198... 

Van Lint C, Emiliani S, Ott M, Verdin E (1996a) Transcriptional activation and chromatin remodeling of the HIV-1 promoter in response to histone acetylation. EMBO J 15 1112-1120 Van Lint C, Emiliani S, Verdin E (1996b) The expression of a small fraction of cellular genes is changed in response to histone hyperacetylation. Gene Expr 5 245-53 Van Lint C, Amelia CA, Emiliani S, John M, Jie T, Verdin E (1997) Transcription factor binding sites downstream of the human immunodeficiency virus type 1 transcription start site are important for vims infectivity. J Virol 71 6113-6127... 

Blander G, Guarente L (2004) The Sir2 family of protein deacetylases. Annu Rev of Biochem 73 417 35 Brinkmann H, Dahler AL, Popa C, Serewko MM, Parsons PG, Gabrielli BG, Burgess AJ, Saunders NA (2001) Histone hyperacetylation induced by histone deacetylase inhibitors is not sufficient to cause growth inhibition in human dermal fibroblasts. J Biol Chem 276 22491-22499... 

But what should happen upon histone hyperacetylation if nucleosomes, on average, do not overtwist DNA Then no change in (ALkn) should be observed. 

Finally, targeted active demethylation has been put forward as an explanation for the unmethylated state of CpG islands (Fig. 3e). In this model, features of active chromatin structure (e.g., histone hyperacetylation) cause active demethylation of associated sequences [43,44]. Based on a broad analysis of existing data, Szyf... 

Oliva, R., Bazett-Jones, D.P., Locklear, L., and Dixon, G.H. (1990) Histone hyperacetylation can induce unfolding of the nucleosome core particle. Nucleic Acids Res. 18(9), 2739-2747. 

Hinnebusch BE, Meng S, Wu JT, Archer SY, Hodin RA. (2002) The effects of short-chain fatty acids on human colon cancer cell phenotype are associated with histone hyperacetylation. JNutr 132 1012-1017. 

Van Lint C, Emiliani S, Verdin E. (1996) The expression of a small fraction of cellular genes is changed in response to histone hyperacetylation. Gene Expression 5 245-253. 

Wu JT, Archer SY, Hinnebnsch B, Meng S, Hodin RA. (2001) Transient vs. prolonged histone hyperacetylation Effects on colon cancer cell growth, differentiation, and apoptosis. Am J Physiol Gastrointest Liver Physiol 280 G482-G490. 

The first functional cell-based assay for the determination of pan-histone deacetylase activity was achieved by detecting hyperacetylated histones by Western blotting. The histone acetylation level in cells offers a measure of candidate HDACI activity and has been linked to antiproliferative and cytotoxic effects. Beckers et al. used a cellular histone hyperacetylation assay for quantification of the cellular efficacy of HDACIs using the Cellomics Array Scan II platform in 96 wells [14]. The program... 

HDAC inhibition [47], as growth of HCT-8 colon carcinoma cells is inhibited by CI-994 (IC50 = 4.7 J.M), with simultaneous dose-dependent increases in histone hyperacetylation. In vitro work also demonstrated that HDAC could be inhibited 50% at 25-50 pM. 

Glauben R, Batra A, Fedke LZeitzM, Lehr HA, Leoni F, Mascagni P, Fantuzzi G, DInarelloCA, Siegmund B Histone hyperacetylation is associated with amelioration of experimental colitis In mice. J Immunol 2006 176 5015-22. 

Figure 3. Role of enhancers and histone acetylation in regulating gene expression. A plasmid-borne reporter gene was either driven by the tk promoter (Promoter) or was coupled with the FI 01 enhancer (Enhancer). In some cases the embryos were also cultured in the presence of butyrate, which induces histone hyperacetylation (Promoter-FButyrate, Enhancer-FButyrate). Either male pronucleus (Male PN), female pronucleus (Female PN), or zygotic nucleus (two-cell) was injected. When one-cell embryos were injected, they were cultured in the presence of aphidicolin to a time that corresponded to the mid to late Iwo-cell stage. The data are expressed relative to the amount of luciferase activity detected in the male pronucleus of an S-phase-arrested, one-cell embryo and were taken from Wiekowski et al., 1993.

McGhee J, Nickol J, Felsenfeld G, Rau D (1983) Histone hyperacetylation has little effect on the higher order folding of chromatin. Nucleic Acids Res 11 4065-4075... 

What is the relevance of these observations to transcriptional control If, indeed, the tails become more loosely associated with DNA upon hyperacetylation, it is possible that the underlying DNA becomes more accessible to nonhistone regulators. In vitro experiments with purified chromatin components and particular transcriptional regulators (A. Wolffe, J. Workman, and their colleagues) have found that histone hyperacetylation potentiates binding to nucleosomal substrates by such proteins as TFIIIA, Gal4, and USF. Whether such potentiation of binding occurs in vivo is unknown. 

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