The chromatin-associated enzyme PARP1 has previously been suggested to ADP-ribosylate histones, but the specific ADP-ribose acceptor sites have remained enigmatic. Here, we show that PARP1 covalently ADP-ribosylates the amino-terminal histone tails of all core histones. Using biochemical tools and novel electron transfer dissociation mass spectrometric protocols, we identify for the first time ...

In this study the effect of a methylated derivative of nitrogen mustard (mechloroethamin) on solubilized and reconstituted chromatin was investigated using UVNis spectroscopy, DNA and SDS gel electrophoresis and densitomeoic scanning techniques, The results indicated that the 210 and 260 nm absorbances of reconstituted chromatin were decreased in a dose-dependent manner after treatment wit...

Central to eukaryotic cellular support such as transcription regulation and chromatin structure are DNA interactions with the nucleosome histone core. The interactions of the histone core with DNA are currently understood partially at best, due in part to the wide range of DNA sequence effects involved in the formation of stable nucleosomes. This paper presents a high-performance computational ...

The epigenetic alterations like histone modifications , DNA methylation and others remarkable categories  including nucleosome remodeling and RNA mediated targeting have been strongly investigated  recently .In this way , beside the notable importance of DNA methylation ,the histone modifications are the most important issues in the  tumorogenesis and cancer progression. Moreover...

Imagine trying to stuff about 10,000 miles of spaghetti inside a basketball. Then, if that was not difficult enough, attempt to find a unique one inch segment of pasta from the middle of this mess, or try to duplicate, untangle and separate individual strings to opposite ends. This simple analogy illustrates some of the daunting tasks associated with the transcription, repair and replication of...

In this study the effect of the alkylating agent, sulfur mustard, on calf thymus chromatin was investigated using UV/Vis spectroscopy, gel electrophoresis and thermal denaturation techniques. The results show that treatment of isolated chromatin with sulfur mustard releases histones from the core particles but does not affect histone H I and nonhistone chromosomal proteins. The content of ...

In recent years, the chromatin field has witnessed a renewed interest in histone variants as pertaining to their structural role, but mainly because of the functional specificity they impart to chromatin. In this review, I am going to discuss several of the most recent structural studies on core histone (H2A.Bbd, H2A.Z, H2A.X, macroH2A, H3.3, CENP-A) and linker histone variants (histone H1 micr...

We describe High-throughput Histone Mapping (HiHiMap), a high-throughput imaging method to measure histones and histone posttranslational modifications (PTMs) in single cells. HiHiMap uses imaging-based quantification of DNA and cyclin A to stage individual cells in the cell cycle to determine the levels of histones or histone PTMs in each stage of the cell cycle. As proof of principle, we appl...

the epigenetic alterations like histone modifications , dna methylation and others remarkable categories  including nucleosome remodeling and rna mediated targeting have been strongly investigated  recently .in this way , beside the notable importance of dna methylation ,the histone modifications are the most important issues in the  tumorogenesis and cancer progression. moreover, the fluctuati...

The gel-filtration behaviour of calf thymus histone fraction F2(b) was studied at three different salt concentrations (0.01m-, 0.10m- and 1.00m-sodium chloride) and two different pH ranges (pH3-4 and pH6.7-7.1). Other histone fractions [F1, F2(a) and F3] were also utilized to assist interpretation of the data. It was found that the Stokes radius of histone fraction F2(b) was not significantly c...