1. A procedure is presented for large scale fractionation of arginine-rich histones by exclusion chromatography. With this method, 2 to 3.5 g of histone Fractions 2a and 3 were fractionated. The two fractions contained the same histone components, but they differed in the amounts of each component. 2. In histone Fraction 2a, the glycine-rich, arginine-rich (GAR) histone accounted for approximat...

Histone H2AX is a histone H2A variant that is ubiquitously expressed throughout the genome. It plays a key role in the cellular response to DNA damage and has been designated as the histone guardian of the genome. Histone H2AX deficiency decreases genomic stability and increases tumor susceptibility of normal cells and tissues. However, the role of histone H2AX phosphorylation in malignant tran...

We have examined the distribution of histone H1 in oocytes and preimplantation embryos of the mouse, using a polyclonal antibody raised against the histone H1 subtypes present in somatic cells. Immunofluorescence and immunoblotting analyses failed to detect somatic histone H1 in germinal vesicle (GV)-stage oocytes. In contrast, somatic histone H1 was detectable by immunofluorescence in the nucl...

Post-translational addition of methyl groups to the amino terminal tails of histone proteins regulates cellular gene expression at various stages of development and the pathogenesis of cellular diseases, including cancer. Several enzymes that modulate these post-translational modifications of histones are promising targets for development of small molecule drugs. However, there is no promising ...

FACT, a heterodimer of Spt16 and Pob3, is an essential histone chaperone. We show that the H2A-H2B binding activity that is central to FACT function resides in short acidic regions near the C termini of each subunit. Mutations throughout these regions affect binding and cause correlated phenotypes that range from mild to lethal, with the largest individual contributions unexpectedly coming from...

Histones are small polycationic proteins complexed with DNA located in the cell nucleus. Upon apoptosis they are secreted from the cells and react with extracellular polyanionic compounds. Actin which is a polyanionic protein, is also secreted from necrotic cells and interacts with histones. We showed that both histone mixture (histone type III) and the recombinant H2A histone bundles F-actin, ...

Histone H2AX is a histone H2A variant that is ubiquitously expressed throughout the genome. It plays a key role in the cellular response to DNA damage and has been designated as the histone guardian of the genome. Histone H2AX deficiency decreases genomic stability and increases tumor susceptibility of normal cells and tissues. However, the role of histone H2AX phosphorylation in malignant tran...

Aging can be defined as a decline of physiological function that is more difficult to reverse, characterized by the loss integrity tissues, organs, and cells an organism over time. Normal aging associated with structural functional changes in brain, involving neuronal apoptosis, synaptic structure, neurotransmission, metabolism alterations, leading impairment sleep, cognitive functions, memory,...

Eukaryotic chromatin is highly dynamic and turns over rapidly even in the absence of DNA replication. Here we show that the acidic histone chaperone nucleosome assembly protein 1 (NAP-1) from yeast reversibly removes and replaces histone protein dimer H2A-H2B or histone variant dimers from assembled nucleosomes, resulting in active histone exchange. Transient removal of H2A-H2B dimers facilitat...

Transcription by RNA polymerase II is accompanied by dynamic changes in chromatin, including the eviction/deposition of nucleosomes or the covalent modification of histone subunits. This study examined the role of the histone H3/H4 chaperones, Asf1 and HIR, in histone mobility during transcription, with particular focus on the histone exchange pathway, using a dual histone expression system. Th...