Histone carbonylation in vivo and in vitro

Abstract

Non-enzymic damage to nuclear proteins has potentially severe consequences for the maintenance of genomic integrity. Introduction of carbonyl groups into histones in vivo and in vitro was assessed by Western blot immunoassay and reductive incorporation of tritium from radiolabelled NaBH4 (sodium borohydride). Histone H1 extracted from bovine thymus, liver and spleen was found to contain significantly elevated amounts of protein-bound carbonyl groups as compared with core histones. The carbonyl content of nuclear proteins of rat pheochromocytoma cells (PC12 cells) was not greatly increased following oxidative stress induced by H2O2, but was significantly increased following alkylating stress induced by N-methyl-N´-nitro-N-nitrosoguanidine or by combined oxidative and alkylating stress. Free ADP-ribose, a reducing sugar generated in the nucleus in proportion to DNA strand breaks, was shown to be a potent histone H1 carbonylating agent in isolated PC12 cell nuclei. Studies of the mechanism of histone H1 modification by ADP-ribose indicate that carbonylation involves formation of a stable acyclic ketoamine. Our results demonstrate preferential histone H1 carbonylation in vivo, with potentially important consequences for chromatin structure and function.

Glycoxidation of histone proteins in autoimmune disorders

“…Many conformational changes induced by glyoxidation reactions have been reported with roles in a variety of pathological complications [22,25,45,51,52,63]. Glycation of histone is believed to influence the integrity of genome [24].…”

“…Various methods for glycation studies have been developed and a variety of procedures for estimating the generation of advanced glycation by-products in histones have been formulated. Many modification sites have been detected and sequenced [12,13,[19][20][21][22][23][24][25][26]. Many conformational changes induced by glyoxidation reactions have been reported with roles in a variety of pathological complications [22,25,45,51,52,63].…”

“…ADP ribose induces significant level of carbonylation in-vivo in histones following an alkylating stress. Methods characterizing glyoxidation damage to histones, quantification of the amount of protein-bound carbonyls and carbonyl background levels on histones extracted from bovine tissue have shown a higher presence of protein bound carbonyls in the histone H1 derived from bovine thymus, liver and spleen as compared to that in the core histones from the same organs [24]. Attachment of ADP-ribosyl residues in hepatoma cells significantly retards the electrophoretic mobility of the nuclear protein [30].…”

“…The alterations in the histone proteins have been studied using various biophysical and biochemical techniques like radio-labelling [19], NMR spectroscopy [19], fluorescence spectroscopy [20,21], fourier transform infrared spectroscopy [20,21], circular dichroism [20,22], Xray irradiation [23], electrophoresis [20,21,24], Western blotting [12], immunoassays [25], liquid chromatography-mass spectrometry (LC-MS) and matrix-assisted laser desorption/ionization (MALDI-MS/ MS) [13], and reversed-phase HPLC [26] It was in late 70s and in 80s that some workers suggested Schiff base formation and browning reactions in histone proteins on the pattern of other glycated proteins, thus opening vistas of studies on glyoxidative damage to nuclear proteins [27][28][29][30][31][32][33]. The term 'glycohistone' was coined by Jobst et al in 1991 after they detected histone glycation in hepatic nuclei of patients dying of decompensated diabetes [34].…”

The function of the epigenome in cell reprogramming

“…The amino and carboxy termini of the histones (histone tail), protruding from the nucleosome, play an essential role in controlling the folding into a higher-order structure, and are the target for posttranscriptional modifications (Fig. 1A), including acetylation [41,42], methylation [43,44], phosphorylation [45], ubiquitination [46], sumoylation [47], carbonylation [48], PARylation [49,50] and others. Adding to the complexity is the fact that the histone tail can carry more than one acetyl or methyl marks at certain amino acid residues.…”